renamed setFrom to resetFrom
- control and observable sensor now reset themsekves from in passed
  state, so the light capable entity no longer needs to deal with those
  details - it is specific to control/sensor
- setEnabled changed in base control to allow calling enable and disable
  all the time - added test case to GpioControlTestCase to cover that -
  e.g. setEnabled(false) still calls disable, which in turn should
  switch off the control
setSwitchedOn moved to BaseControl
- removed from MockControl therefore
- updated a javadoc of ControlObserver a little
logging added to factories and specifications and sensors