FIX: augeas runtime optimization (~4 sec per augeas resource)

Nice module, but running it to configure ~50 shares it took us about 360 sec to configure the shares and ~70 sec for an empty run (after all shares got configured).

The fix reduces the lens loaded and files the augeas resources are aplied to(/etc/samba/smb.conf).
Now the puppet run takes us ~60 sec to configure all the shares and ~30 sec for an empty run