[dev] hooks

[Marko Djukic]

would it make sense to have something like a Horde::callHook($app, $function)
which would check if it can require that app's hook file and call the function.
this would cut out a lot of the repetitive code of including the hooks file,
checking if the function exists, calling the function etc.
is there any advantage to distributing the functions to their corresponding
app's hook file? if not then just a simple callHook($function), and stick with
the one /horde/config/hooks.php

marko