Implement a helper script for zone reloads

It turns out the `rndc` command that was intended to reload a managed zone
wasn't working (see PR #91 for reference) if more than one view included the
zone. The helper script is really just a wrapper around the `rndc` command
itself, it translates its final parameter into a domain/class/view tuple and
pass the leading parameters and the tuple to `rndc`.

data/common.yaml

@@ -1,7 +1,6 @@
 ---
 bind::defaults::supported: false
 bind::defaults::random_device: '/dev/random'
-bind::defaults::rndc: true
 
 bind::forwarders: ''
 bind::dnssec: true