Backup geowiki's data-private bare repository

The bare repository is not in gerrit, as it contains "foundation only"
data, and we do not trust gerrit to keep it private. So we backup the
repository separately.

Change-Id: Icbb54de9ca353abad31828bf2c7a1f4524ff4b02
Merge "Backup geowiki's data-private bare repository" into production