Fix issue with mysql not restarting on new bind_ip

Addresses: bug #1277041

By default mysql binds to 127.0.0.1. Setting the bind_ip attribute to
something else, as we do in the ops-database cookbook before calling the
mysql::server recipe, causes the my.cnf to be populated with the correct IP.

However, because of this bug in the upstream mysql cookbook:
https://tickets.opscode.com/browse/COOK-4161
mysql does not get restarted (it only gets reloaded)
and so the new bind_ip does not take effect.

This commit adds a workaround until the upstream bug is fixed. The
workaround directly modifies the template resource from the resource
collection to add a 'restart mysql' notification.

Change-Id: I4f59e9f7fecb5040532948d0bb07d49385280a48