Add and update .gitignore & .gitlab-ci.yml templates for 8.14

Following https://gitlab.com/gitlab-org/gitlab-ce/issues/24134

See merge request !7272

[ci skip]

Adds JavaScript validation for group path editing

## What does this MR do?

- Prevents group_edit form submission when special characters are included in the new group name
- Enhances gl_field_errors to support this use case and be more re-usable. 

## Are there points in the code the reviewer needs to double check?

**The implementation of validation is here: https://gitlab.com/gitlab-org/gitlab-ce/commit/73d997046cac376ccdbcaac6f183002bc19b9a1f**

The rest of the diff for this MR is augmenting gl_field_errors

## Why was this MR needed?

- Currently we allow submission and a 500 error is returned. 

## Screenshots (if relevant)
![2016-10-21_14.11.21](/uploads/2bef5764d3f2429dd0f900661153eef7/2016-10-21_14.11.21.gif)
## Does this MR meet the acceptance criteria?

- [x] [CHANGELOG](https://gitlab.com/gitlab-org/gitlab-ce/blob/master/CHANGELOG.md) entry added
- [x] [Documentation created/updated](https://gitlab.com/gitlab-org/gitlab-ce/blob/master/doc/development/doc_styleguide.md)
- [x] All builds are passing
- [x] Conform by the [merge request performance guides](http://docs.gitlab.com/ce/development/merge_request_performance_guidelines.html)
- [x] Conform by the [style guides](https://gitlab.com/gitlab-org/gitlab-ce/blob/master/CONTRIBUTING.md#style-guides)
- [x] Branch has no merge conflicts with `master` (if it does - rebase it please)
- [x] [Squashed related commits together](https://git-scm.com/book/en/Git-Tools-Rewriting-History#Squashing-Commits)

## What are the relevant issue numbers?

Closes https://gitlab.com/gitlab-org/gitlab-ce/issues/23564, https://gitlab.com/gitlab-org/gitlab-ce/issues/19756, https://gitlab.com/gitlab-org/gitlab-ce/issues/19736, https://gitlab.com/gitlab-org/gitlab-ce/issues/23922

See merge request !7041

Don't include Gitlab::Routing.url_helpers on top-level namespace (fix error for url_for)

## What does this MR do?

Tries to fix:

```
     ActionView::Template::Error:
      arguments passed to url_for can't be handled. Please require routes or provide your own implementation
```

One of the failed build: https://gitlab.com/gitlab-org/gitlab-ce/builds/5825797

See merge request !7265

Expose more info for SystemHooks

See merge request !6964

Update "Installation from source" guide for 8.14.0

Following the steps from https://gitlab.com/gitlab-org/release-tools/blob/master/doc/release-candidates.md#creating-rc1.

See merge request !7271

Signed-off-by: Rémy Coutable <remy@rymai.me>

Fix symlink vulnerability in Import/Export

Replaces https://dev.gitlab.org/gitlab/gitlabhq/merge_requests/2018 made by @james

Fixes https://gitlab.com/gitlab-org/gitlab-ce/issues/23822

See merge request !2022
Signed-off-by: Rémy Coutable <remy@rymai.me>

Fix Import/Export foreign key issue to do with project members

Cleans-up any foreign keys in `ProjectMember` - same as we do with the rest of the models when importing.

Fixes https://gitlab.com/gitlab-org/gitlab-ce/issues/23837 and https://gitlab.com/gitlab-org/gitlab-ce/issues/23739

See merge request !2020
Signed-off-by: Rémy Coutable <remy@rymai.me>

[ci skip]

[ci skip]

Add a `--force` option to bin/changelog

See merge request !7252

Check that JavaScript file names match convention

## What does this MR do?

Introduce a new ESLint rule to check JavaScript file names.

## What are the relevant issue numbers?

fixes #23118

See merge request !7238

Updated Sortable JS plugin

## What does this MR do?

Updates Sortable JS plugin for issue boards. The older version stopped the issue cards being draggable.

## What are the relevant issue numbers?

Closes #23048

See merge request !6734

Removes spaces in log messages.

refs:
- 6f7ccea6
- 7121a58e
- f54bf003

none of them seem to have added extra space deliberately (commit message is about something else)

## Why was this MR needed?

The spaces caused confusion when trying to analyze the logs, there was no space in user name, but log message indicated there was.

See merge request !7223

Update examples in changelog docs to use single quotes around title

[ci skip]

See merge request !7246

[ci skip]

Removed z-index for filters on issue boards

## What does this MR do?

I dont know how this is has only just become a problem, but when the sidebar is open the filters on issue boards overlap it.

## Screenshots (if relevant)

### Before

![Screen_Shot_2016-11-02_at_09.50.59](/uploads/430ec15249b866999e83fe402cd9bd35/Screen_Shot_2016-11-02_at_09.50.59.png)

### After

![Screen_Shot_2016-11-02_at_09.49.40](/uploads/3a417570a874197ce4b66cbfadbf8181/Screen_Shot_2016-11-02_at_09.49.40.png)

See merge request !7235

Fix edit button in wiki

## What does this MR do?

Fix edit button in wiki.

## Are there points in the code the reviewer needs to double check?

## Why was this MR needed?

## Screenshots (if relevant)

### Show Wiki

![wiki_show](/uploads/7633b7de9921cb8abe688a11883b8d1d/wiki_show.png)

### Edit Wiki

![wiki_edit](/uploads/2529bb1d5eb5b33ef97da89e634bb8ad/wiki_edit.png)

## Does this MR meet the acceptance criteria?

- [x] [CHANGELOG](https://gitlab.com/gitlab-org/gitlab-ce/blob/master/CHANGELOG.md) entry added
- [ ] [Documentation created/updated](https://gitlab.com/gitlab-org/gitlab-ce/blob/master/doc/development/doc_styleguide.md)
- [ ] API support added
- Tests
  - [ ] Added for this feature/bug
  - [ ] All builds are passing
- [ ] Conform by the [merge request performance guides](http://docs.gitlab.com/ce/development/merge_request_performance_guidelines.html)
- [ ] Conform by the [style guides](https://gitlab.com/gitlab-org/gitlab-ce/blob/master/CONTRIBUTING.md#style-guides)
- [ ] Branch has no merge conflicts with `master` (if it does - rebase it please)
- [ ] [Squashed related commits together](https://git-scm.com/book/en/Git-Tools-Rewriting-History#Squashing-Commits)

## What are the relevant issue numbers?

Closes #13444

See merge request !7143

Add a bin/changelog script and changelog documentation

See merge request !7098

Make ESLint ignore instrumented files for coverage analysis

## What does this MR do?
 
Ignore files in `coverage-javascript/` directory.

## Why was this MR needed?

When running ESLint after coverage analysis locally, it led to many linting errors. CI was not affected (ESLint and coverage are different jobs).

See merge request !7236

Update diffy gem to 3.1.0

See merge request !7184

Use the server's base URL without relative URL part when creating links
in JIRA

Closes #17846

See merge request !6143

Signed-off-by: Rémy Coutable <remy@rymai.me>

Replace links to the `Merge request description format` section with
up-to-date instructions on using the MR template built into the UI.

The `Merge request description format` section was removed in 2f7e28d1,
but links were left in the table of contents and in the MR description
instructions. Presumably, the section was removed because MR templates
are now provided by the GitLab UI.

See merge request !7228

Explains the problem instead of Yelling.

The relevant part that fails is in gitlab-shell:
https://gitlab.com/gitlab-org/gitlab-shell/blob/v3.6.6/hooks/post-receive#L8

See merge request !7224

[ci skip]

Updates rack-attack gem to 4.4.1

See merge request !7186

GitLab 8.13 not 13

cc// @felipe_artur

See merge request !7234

Fix gdb backtrace command

See merge request !7227

add container registry images to not exported list

See the general Documentation guidelines http://docs.gitlab.com/ce/development/doc_styleguide.html

## What does this MR do?

Clarify that images are not exported

See merge request !7187

This MR adds support for the `token` attribute in the project hook API.

Feature requested on a dependant project: https://github.com/gpocentek/python-gitlab/issues/170

See merge request !7220

Added guide for upgrading Postgres using Slony

## What does this MR do?

This adds a guide for upgrading PostgreSQL using Slony.

## Are there points in the code the reviewer needs to double check?

Spelling, grammar, etc

## Why was this MR needed?

This process is not documented and we'll need to provide steps on how to do this before we start shipping PostgreSQL 9.6 with omnibus-gitlab.

## Does this MR meet the acceptance criteria?

- [x] [CHANGELOG](https://gitlab.com/gitlab-org/gitlab-ce/blob/master/CHANGELOG) entry added
- [x] [Documentation created/updated](https://gitlab.com/gitlab-org/gitlab-ce/blob/master/doc/development/doc_styleguide.md)
- [x] Conform by the [style guides](https://gitlab.com/gitlab-org/gitlab-ce/blob/master/CONTRIBUTING.md#style-guides)
- [x] Branch has no merge conflicts with `master` (if you do - rebase it please)
- [x] [Squashed related commits together](https://git-scm.com/book/en/Git-Tools-Rewriting-History#Squashing-Commits)

cc @pcarranza @marin @axil

See merge request !6711