Updated samples to use Immutable geometry and Viewpoint
Updated desktop samples to use Immutable geometry and Viewpoint
Updated phone samples to use Immutable geometry and Viewpoint
Fixed issues caused by geometry changes
Fixed Simplify sample for Store and Phone.

Sample was using MapView.Extent.GetCenter right after MapView.ExtentChanged so it got wrong values that we were expecting. Changed to use MapView.NavigationCompleted instead.
Fixed generalize sample
Merge pull request #15 from Esri/dotMorten/ImmutableGeometry

Updates samples to treat geometry immutable