Support adding and removing branches and tags

Update config.yml.example for grammar

The previous commit has the code addition to support adding and removing branches and
tags in a repository - This commit ensures basic test cases are supported.

This commit adds support to create and remove branches and tags from gitlab-shell.

The code style was followed as closely as possible to the original.

The purpose of this commit is that I will be adding support to the Gitlabhq (Gitlab) project
in order to allow adding and removing of branches and tags through their API.

Logger

added optional argument so to override default repo location

propably better ssh-key id finding in ARGV

Add ca_file/ca_path configuration options.

Add message that repes_path should be real path

Regex used in rm-key command is too lax

Basically the issue is that 'gitlab-shell rm-key key-2' removes all keys that match "key-2" pattern.
"key-20", "key-25", etc.
This change makes the regex used in the sed command more strict.