Adding authenticated public mode (internal).

Added visibility_level icons to project view (rather than just text).
Added public projects to search results.
Added ability to restrict visibility levels standard users can set.
Merge branch 'authenticated_public_mode' of https://github.com/jhollingsworth/gitlabhq into feature/internal_projects

Conflicts:
	app/models/project.rb

Signed-off-by: Dmitriy Zaporozhets <dmitriy.zaporozhets@gmail.com>
Improve UX of project visiblity level. Improve "Public Access" help page

Signed-off-by: Dmitriy Zaporozhets <dmitriy.zaporozhets@gmail.com>
Restyle public access help page

Signed-off-by: Dmitriy Zaporozhets <dmitriy.zaporozhets@gmail.com>
Remove unnecessary \" symbols

Signed-off-by: Dmitriy Zaporozhets <dmitriy.zaporozhets@gmail.com>
Merge pull request #5701 from gitlabhq/feature/internal_projects

Feature: Internal projects