Find and kill instances of `event.component['uid']` et al

[tobixen]

Ref #94 we should trust that event.id gives the uid of an object (really? Always, always? Even if the uid is changed by doing event.data=... or event.component['uid'] = 'new value'? Perhaps it's needed to do more research on this?).

Still, I'm doing things like event.component['uid'] several places. Those should be replaced with event.id`

[tobixen]

I found that we cannot trust event.id to always give the correct uid, so this needs more fixing first.

[tobixen]

Maybe event.id should be a property?