Revert "[client][ios][offline] revert ios offline/v2.0 changes"

This reverts commit 7832f0288366a044e4ab04649c7f1948f98b07c5.
Merge branch 'dev' into offline
Update Xamarin.iOS quickstart: add offline support, minor UI changes
Updated Xamarin.Android quickstart: add offline support
Windows C# quickstart: add commented-out code for adding offline support
Xamarin Android quickstart: add link to conflict handling tutorial
Xamarin.iOS quickstart: add comment & URL for info on conflict handling
Add doccomments to PullAsync overloads
Merge pull request #506 from lindydonna/dev

Add doccomments to PullAsync overloads
Remove progress spinner from Xamarin.Android quickstart
Remove progress indicator from Xamarin.iOS quickstart
Update Xamarin.iOS quickstart to always sync after local edits
Update Xamarin.Android quickstart to sync after local edits
Merge branch 'dev' into offline
Merge branch 'offline' of https://github.com/Azure/azure-mobile-services into offline