* Add power attribute to switch.
* Move device_state_attributes into base class.
* Fix imports following refactor.
* Bump pyvera version - should add contributed support for older (UI5) version dimmers and locks.
* Refactor device lookup to be based on vera classes, push category back into library.
* Add generic power attribute, fix inherited class order bug.
* Tidy.
Greg Dowling
rhooper
Paulus Schoutsen
pavoni