Add settings for user permission defaults

“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.
Merge branch 'add-defaults-create-group-team' of https://github.com/dmedvinsky/gitlabhq into dmedvinsky-add-defaults-create-group-team

Conflicts:
	config/gitlab.yml.example
Merge branch 'dmedvinsky-add-defaults-create-group-team'