gitlab: moved repositories directory to /home/git/data/repositories
gitlab: moved gitlab-satellites directory to /home/git/data/gitlab-satellites
gitlab: moved backups directory to /home/git/data/backups
gitlab: moved uploads directory to /home/git/data/uploads
gitlab: moved .ssh directory to /home/git/data/.ssh
README: added directory structure change notice for existing users
Merge branch 'feature/unified-data-store'