Potential solution for current `rake gitlab:app:backup_restore` issues.

Created by: mrrooijen

Modified the repo_dump and repo_restore rake tasks to properly dump and restore repositories based on their path rather than their (project) name. The project name can be uppercase and may contain spaces. This caused the repository to be restored as a different path that it was initially created as, thus, breaking the git remote and the web interface can no longer detect the repository either because it searches by path and not by name. Also, when restoring the permissions are incorrect making it impossible to push new commits to the remote repository. So now on success it'll set the correct permissions (but requires that the gitlab user has sudo privileges, or this task must be executed as root).