cleaning up bind9 salt formula.
syncing with updates from upstream.
restoring map.user and map.group for defaults.
Merge pull request #7 from garethgreenaway/master

Cleaning up the bind9 salt formula.
Added a way to control the listen-on directive and initial support for query-source, notify-source and transfer-source
Merge remote-tracking branch 'upstream/master'

Conflicts:
	bind/config.sls
	bind/files/debian/named.conf.options
	bind/files/redhat/named.conf.local