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.

This option allows to disable users from changing their username.

This is very usefull in environments using strong internal authentication methods like ldap, pam or shibboleth.

You can allow users to change theyr username in these environments, but then new users (users loging in first time) is blocked from gitlab is her username exists.