Legend based on SymbolDisplay:

   - LegendItemViewModel.SymbolSwatch property removed
   - LegendItemViewModel.GeometryType property made public
   - LayerItemViewModel/Legend optimized to avoid useless LayerItemsSource changes (and so useless swatch creations)
   - LegendItemTemplate based on SymbolDisplay
TemplatePicker based on SymbolDisplay:

  - TemplateItem (private class but used for Binding):
      . Removed Swatch Property
      . Added GeometryType and Symbol properties
  - Default template picker styles based on  SymbolDisplay
  - Use Loaded/Unloaded events to subscribe/unsubscribe to layers events
Merge branch 'dom/issue57_SymbolDisplay' into dom/Legend_UseSymbolDisplay
Updated due to SymbolDisplay namespace change.
Merge branch 'dom/issue57_SymbolDisplay' into dom/TemplatePicker_UseSymbolDisplay
Updated due to SymbolDisplay namespace change.
Added WinPhone and Desktop OAuthAuthorize component.
Merge branch 'v.next' into dom/issue64_OAuthAuthorizeComponents
Remove dependency properties SwatchDpi, DefaultWidth and DefaultHeight
Merge branch 'dom/issue57_SymbolDisplay' into dom/TemplatePicker_UseSymbolDisplay

Conflicts:
	src/Common/Esri.ArcGISRuntime.Toolkit/Controls/TemplatePicker/TemplatePicker.cs
Merge branch 'dom/issue57_SymbolDisplay' into dom/Legend_UseSymbolDisplay
Remove setting of DefaultWidth and DefaultHeight.
Merge branch 'v.next' into dom/TemplatePicker_UseSymbolDisplay

Conflicts:
	src/Common/Esri.ArcGISRuntime.Toolkit/Controls/TemplatePicker/TemplatePicker.cs
Merge branch 'v.next' into dom/TemplatePicker_UseSymbolDisplay
Merge branch 'dom/issue57_SymbolDisplay' into dom/Legend_UseSymbolDisplay
Merge branch 'v.next' into dom/issue64_OAuthAuthorizeComponents
Move the OAuthAuthorize components in Security namespace for consistency with the coming WinPhoneChallengeHandler.
Support for the callbackURL which depends on the organization selected by the user at run time.
Desktop : Fixed xml generation and added SymbolDisplay sample
Added SymbolDisplay for phone and store