Reverted the bind restart command to `sudo rndc reload` since we cannot check and reload in one command. (Double ampersand is escaped).

Moved supported TTL and TYPE options to helper functions and use these in a views field handler to display friendly TTL labels instead of seconds.

Added a dot as an allowed DNS character.

Make sure we remove any remaining DNS nodes when we uninstall the module. It results in broken associations when the module is enabled again later.

Removed update TTL as a hosting action and implemented it as a regular VBO action. (It can safely operate direct on the DNS nodes.)