The recent angular update changed the format of the hash keys.
They're now in the format 'object:123' (etc), which isn't a valid
CSS class name any more, but we used the $$hashKey as such.
I used this opportunity to introduce a bit of abstraction there as well
Requires turning IrcUtils into an Angular service, because the global variable
trick won't work with use strict.
Reuse is still easily possible by removing the angular wrapping around it.
