Navigation improvements
Merge branch 'develop' into feature/navigation
Lots of navigation improvements (especially on the Universal App platforms)
Merge branch 'feature/navigation' into develop
(*) CTL-428 Simplified navigation on all platforms. This means that Catel will no longer keep viewmodels in memory to provide a back stack. This is to make the navigation the same on all platforms. If there is a need to keep state, the developer will be responsible to implement that
(+) CTL-436 Add generic ICatelCommand interfaces
NullReference fix in LocationService for Android