Add GoodJob Dashboard and User#role

[mediafinger]

• add User(!) Roles:
  • admin, _can access the good_job interface and other internal UIs, is also editor, moderator and accountmanager
  • account_manager, can create and manage teams and users and is an editor
  • moderator, can flag, hide, edit content that violates the TOS and flag or block users and is an editor
  • editor, can update content of the homepage and I18n resources
  • user, the default role, a user without any special permissions
• configure GoodJob
• render GoodJob UI

TODO

• [x] protect GoodJob UI access, so only a user with the role admin has access