Be more reactive and act when a domain is enable

[camlafit]

Use hook system to catch all creation/delete sub-domain

[camlafit]

Looks a bit hard to do better :/
We can act we an hourly cron or use hook.

With cron looks correct to limit hourly script, to prevent any overload
with hool we can't catch when domain is up, as we cant warranty to execute hook after apache/bind reload