Before we have only owner_id to determine group owner
With multiple owners per group we should get rid of owner_id in group.
So from now @group.owner will always be nil but
@group.owners return an actual array of users who can admin this group

GITLAB-1262

Change-Id: I690cb8ea294df53ebe8405a519c23c501af2c21a

Conflicts:
	app/models/user.rb
	config/initializers/1_settings.rb
	spec/models/user_spec.rb

Change-Id: Ia723321a5cb05deb626d34c7d8d78194e049b1f0

Change-Id: Ib4eb533dff5c722fe559330e4aa71b5d5baf6fb8

-calling build_user will now apply defaults and only override them if as: :admin is set

Change-Id: Id1d938c0967752ecc14370af54f2d88128d18c44

-API now respects default_projects_limit, default_can_create_group, and default_can_create_team

Change-Id: I059d060d576df1050e5371e707381c5e8c608a7a

Change-Id: I305266fe9acbbb5136adeeb52e7e4e1d6629a30a

Provide UI with explanation what happens when you block or remove user
When remove user - remove all groups where user is an only owner

When block user - remove it from joined groups
Dont remove user from own resources (groups, users)

Apply user project limit only for personal projects. We should not include group projects for user limit

Since masters_projects does not cover most of cases now we use authorized_projects for DeployKey read access

Improve query of authorized_projects. Cache results for authorized_groups, authorized_projects methods

500 error was occured in the following steps:

1. user1 creates new team "team1".
2. Assign team1 to project1.
3. Sign in as admin. This admin is not a member of team1.
4. Open project1 team setting page (/project1/team).
5. Click "team1" link in "Assigned teams" area.
6. 500 error.

Fixed this issue.

Add api to collect owned user projects. Api deploy_key.create: Enable deploy key if it exist in other owned project

“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.