Closes #19968

Closes #14201

This reverts commit 63144cd0, reversing
changes made to 8ab5df9d.

Use RJS to render edit note feature.

Before:

```
Rendered projects/notes/_note.html.haml (27.9ms)
Rendered projects/_zen.html.haml (0.3ms)
Rendered projects/notes/_hints.html.haml (0.7ms)
Rendered projects/_md_preview.html.haml (3.9ms)
Rendered projects/notes/_edit_form.html.haml (6.9ms)
Rendered projects/notes/_note.html.haml (17.7ms)
Rendered projects/_zen.html.haml (0.3ms)
Rendered projects/notes/_hints.html.haml (0.6ms)
Rendered projects/_md_preview.html.haml (3.4ms)
Rendered projects/notes/_edit_form.html.haml (7.0ms)
```

After:

```
Rendered projects/notes/_note.html.haml (13.8ms)
Rendered projects/notes/_note.html.haml (7.1ms)
Rendered projects/notes/_note.html.haml (9.5ms)
Rendered projects/notes/_note.html.haml (8.5ms)
```

This change reduce at least 6ms * N ('N' - number of notes).

write_ was renamed to create_
modify_  was renamed to update_

So now in update action we have next code

def create
  can?(current_user, :create_issue, @issue)
end

def update
  can?(current_user, :update_issue, @issue)
end
Signed-off-by: Dmitriy Zaporozhets <dmitriy.zaporozhets@gmail.com>

Closes https://github.com/gitlabhq/gitlabhq/issues/9283

Make the following changes to deal with new behavior in Rails 4.1.2:

* Use nested resources to avoid slashes in arguments to path helpers.

Signed-off-by: Dmitriy Zaporozhets <dmitriy.zaporozhets@gmail.com>

Signed-off-by: Dmitriy Zaporozhets <dmitriy.zaporozhets@gmail.com>

Signed-off-by: Dmitriy Zaporozhets <dmitriy.zaporozhets@gmail.com>

Allows previews and uploads in all forms.
Also fixes #1730

  * Remove trailing whitespace
  * Converts hard-tabs into two-space soft-tabs
  * Remove consecutive blank lines