GlusterFS support - Additional domain controllers can now use glusterfs.

This support is experimental and is not enabled by default.

To enable create an empty file before adding any other servers:
touch /opt/karoshi/serversetup/variables/glusterfs

Adding an additional domain controller will now automatically create gluster volumes for:

/var/lib/samba/netlogon
/var/lib/samba/sysvol
/home/applications