This reverts commit 3e991230.

# Conflicts:
#	app/models/project.rb

This reports uses of `File.exists?` and `Dir.exists?`, which were both
deprecated in Ruby and will eventually be removed in favor of
`.exist?`. Also fixes all existing uses of the deprecated methods.

- Enable CI by default for all new projects

Use import_status to track async import status and give feedback to the user

Closes #2388
Closes #2400

These specs also failed when run by themselves before this change, so
we've likely got some kind of cross-test contamination going on.

Allow admins to use restricted visibility levels when creating or
updating projects.

Signed-off-by: NJeroen van Baarsen <jeroenvanbaarsen@gmail.com>

Signed-off-by: NDmitriy Zaporozhets <dmitriy.zaporozhets@gmail.com>

Signed-off-by: NDmitriy Zaporozhets <dmitriy.zaporozhets@gmail.com>

Signed-off-by: NDmitriy Zaporozhets <dmitriy.zaporozhets@gmail.com>

[ci skip]

Signed-off-by: NDmitriy Zaporozhets <dmitriy.zaporozhets@gmail.com>

Signed-off-by: NDmitriy Zaporozhets <dmitriy.zaporozhets@gmail.com>

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.