samba4: Add server side smb.conf template

Signed-off-by: Stéphane Graber <stgraber@ubuntu.com>
bind9: Add the DNS config for samba4

This adds a new bind9 bundle with named.conf and named.conf.options both
as template made to contain what's needed for samba4 integration.

Signed-off-by: Stéphane Graber <stgraber@ubuntu.com>
bcfg2: Update groups-bundles

Signed-off-by: Stéphane Graber <stgraber@ubuntu.com>