Created tests and refactored some code along the way

Added stat graph util spec, refactored code

finsihed up tests and refactors

finsihed up tests and refactors

Jira issues numbering format are like: "PROJECT-1234".
Changed the regular expression to support Jira issues linking, in addition to the normal #123.

Added Jira Issue tracker configuration example

Hackily handle this with a begin block and return a default that matches current use.

Store the secret token in a .gitignored file called ".secret", which is
created by the initializer if it doesn't exist.

Instead of assuming that the Settings.gitlab['user'] home directory is:
/home/git

Obtain the default value from Etc and use that if not set in config.yml.

“Can create groups” and “Can create teams” had hardcoded defaults to
`true`. Sometimes it is desirable to prohibit these for newly created
users by default.

Closing #3614" and "Closing #3574.

update jquery-atwho-rails to v0.3.0

add autocomplete_source action to project for gfm autocomplete

move init_autocomplete layout from head_panel to project_resource

Conflicts:
	config/gitlab.yml.example
	config/initializers/1_settings.rb