* Control backend should be part of the core

* backends should be able to extend diversity-daemon in several ways
	- create new DiversityObject types
	- provide functionalities to existing types
	- export new types and functionalities to dbus

* backends should be dynamically loaded plugins.

* DiversityViewport should have a real overlay.  DiversityOverlay is ugly.

* DiversityNetwork is ugly.  Use DiversityEquipment?

* How to associate DiversityBard with EContact?

* Use fixed-point numbers

* Interpolate AP strength grid