Closes #297 Mark BindingList as Serializable
Switch to using a shared code project for the code.

Update to using assemblies from NuGet.

Update to current Xamarin tools.
Copy SimpleNTier from NET to Mobile folder and start adding Android and iOS apps.
Get the basic customer data to display and edit in iOS and Android.
Merge pull request #313 from rockfordlhotka/master

Merge various updates to master