Extended users API to support updating and deleting users.

Also added tests.
Allow the OmniAuth provider args parameter to pass through as either an Array or a Hash.
Don't setuid the repositories on installation
Don't setuid the repositories (Rake checks)
Fix git group detection for gitolite ssh user.

The tasks gitlab:env:info mixes user and group, and presume as a group 'git'.
However, gitolite group name can be anything.

That patch add the git group name in the config,
and check gitolite.ssh_user group against git.group
(which defaults to 'git', as before this patch, if undefined).

M config/gitlab.yml.example:
  Add 'group' in 'git' section
  Mention default value for the two extra settings
M lib/tasks/gitlab/check.rake:
  Check that gitolite.ssh_user *group* is the one defined in git.group.
  Make sure to default to 'git' as the expected group
    if said group is undefined in the config.
  Note: uses a more complete regexp for the group detection
        (the group can start, end or be in the middle or the list of groups
         of gitolite.ssh_user)
M: config/initializers/1_settings.rb:
  Add default values for gitolite.group and gitlab.user
Use Urls for references in GFM
Use image Urls for Emoji in GFM

Fixes #2617
Fix parsing of ref-like Urls in links and images in GFM

Fixes #2166
Fix markdown for note events
Merge branch 'check_gitlab_in_git_group' of https://github.com/VonC/gitlabhq into VonC-check_gitlab_in_git_group
Fix settings
Fix check.rake to use the new user and group settings
Fix gitolite config checks for old Gitolite versions

Fixes #2608
Merge pull request #2346 from sodabrew/omniauth_configs

Allow the OmniAuth provider args parameter to be passed through
Fix GFM specs
Add SSH custom port support for install/installation.md
Better solution for strict key check
Fix branch remove on automerge
Remove satellites when moving namespace
Fix assign-to-me filter for project issues