Make omnibus the default in repo import docs

doc/raketasks/import.md

@@ -19,15 +19,20 @@ your repositories are located by looking at `config/gitlab.yml` under the `gitla
 New folder needs to have git user ownership and read/write/execute access for git user and its group:
 ```
-$ mkdir new_group
-$ chown git:git new_group
-$ chmod 770 new_group
+# Replace /var/opt/gitlab/git-data with /home/git if you are using an
+# installation from source.
+sudo -u git mkdir /var/opt/gitlab/git-data/repositories/new_group
 ```
 ### Copy your bare repositories inside this newly created folder:
 ```
-$ cp -r /old/git/foo.git/ /home/git/repositories/new_group/
+# Replace /var/opt/gitlab/git-data with /home/git if you are using an
+# installation from source.
+sudo cp -r /old/git/foo.git /var/opt/gitlab/git-data/repositories/new_group/
+
+# Do this once when you are done copying git repositories
+sudo chown -R git:git /var/opt/gitlab/git-data/repositories/new_group/
 ```
 `foo.git` needs to be owned by the git user and git users group.