Update to ServiceStack Android DlLL

Fix for
https://github.com/XForms/Xamarin-Forms-Labs/issues/220#issuecomment-52305572
Added back press to IXFormsApp

This feature is mainly to better support WP8 in page disappearing
situations.
Merge branch 'master' of github.com:XForms/Xamarin-Forms-Labs

Conflicts:

src/Xamarin.Forms.Labs/Xamarin.Forms.Labs.iOS/Xamarin.Forms.Labs.iOS.csp
roj
Added device information for iPad 2G
CheckBox label size for iOS

Draft, corrects the size when checked but have not been able to
determine how to correctly apply at init.

https://github.com/XForms/Xamarin-Forms-Labs/issues/216
iOS CheckBox multiline rendering fixed

https://github.com/XForms/Xamarin-Forms-Labs/issues/216
Added AutoFacContainer

Added implementation for AutoFac IDependencyContainer.
Merge pull request #225 from Qwin/master

Added AutoFacContainer
Updated namespace which was wrong (AutoFac vs Autofac). Added unit tests.
Merge pull request #226 from Qwin/master

Updated namespace which was wrong (AutoFac vs Autofac). Added unit tests. Updated ViewModelNavigation to use strongly typed TViewModel instead of ViewModel.
Initial draft for Camera Preview

Quick basic implementation for Android, iOS to follow. I am not sure
this will be possible at all with WP8 but we shall see…
Added Camera Preview renderer for iOS
Added unit test for iPad versions
Merge branch 'master' of https://github.com/XForms/Xamarin-Forms-Labs
Added Extended Slider control
Modified Segment control to better match Labs' coding styles. Created Segment sample page.
Modified CheckBox sample. Added screen shots
Added screen shots for Slider and SegmentControl
Updated Android ServiceStack DLL
Update to Xamarin Forms 1.2.3.pre1 close #223