adapted current services stuff to use new project import, plus fixes a few issues, updated routes, etc...

This reverts commit 3e991230.

# Conflicts:
#	app/models/project.rb

Favor `unless` over `if` for negative conditions
(or control flow ||).

See #17478

commit 92de6309
Merge: 6c082ede 30f4dcd4
Author: James Lopez <james@jameslopez.es>
Date:   Thu May 19 13:06:34 2016 +0200

    Merge branches 'feature/project-export' and 'feature/project-import' of gitlab.com:gitlab-org/gitlab-ce into feature/project-import

commit 30f4dcd4
Author: James Lopez <james@jameslopez.es>
Date:   Thu May 19 13:02:57 2016 +0200

    uploads export

added better error handling. Also refactored some of the code and fixed a few issues in project_tree_saver

Run ProjectDestroyWorker after pending_delete attribute has been committed to DB