Add a parameter to not restart on config change

[achevalet]

Hi, since 2.0.x requires a reload on all nodes at the exact same time (e.g. when adding a VIP), I would like to have keepalived service managed, ie started at bootstrap, but not restarted when config changes, so I can manage the reload command outside of this module.

What do you think about adding a parameter which allows to notify or not the service when the configuration file is updated? Something like restart_on_change?