Logic cleanup

[rozyczko]

Simplified signalling between proxies and logics.

proxy1 <-> PyQmlProxy <-> proxy2 logic1 <-> LogicController <-> logic2

but

proxy1 -> logic1 only

logic1 -> proxy2 must use signals to notify its own proxy, which in turn communicates with proxy2 logic1 -> logic2 must use LogicController and not call logic2 directly