Reacting to System.IO.FileSystem package version change
1. Moving input formatting related classes to MVC Core.(for tests as well).
2. Cleaning up the IInputFormatter to the final version.
3. Updating the input formatters and the context to be compliant with the IInputFormatter interface.
4. Adding Functional Tests.
- Not cleaning up TempInputFormatterProvider.

Conflicts:
	src/Microsoft.AspNet.Mvc.Core/Formatters/InputFormatter.cs
	src/Microsoft.AspNet.Mvc.Core/Formatters/JsonInputFormatter.cs
	src/Microsoft.AspNet.Mvc.Core/Formatters/TempInputFormatterProvider.cs
	src/Microsoft.AspNet.Mvc.Core/Formatters/XmlDataContractSerializerInputFormatter.cs
	src/Microsoft.AspNet.Mvc.Core/Formatters/XmlSerializerInputFormatter.cs
	src/Microsoft.AspNet.Mvc.Core/Microsoft.AspNet.Mvc.Core.kproj
	src/Microsoft.AspNet.Mvc.Core/ReflectedActionInvoker.cs
	src/Microsoft.AspNet.Mvc.ModelBinding/Microsoft.AspNet.Mvc.ModelBinding.kproj
	test/Microsoft.AspNet.Mvc.Core.Test/Microsoft.AspNet.Mvc.Core.Test.kproj

Conflicts:
	src/Microsoft.AspNet.Mvc.Core/Microsoft.AspNet.Mvc.Core.kproj
	src/Microsoft.AspNet.Mvc.HeaderValueAbstractions/Microsoft.AspNet.Mvc.HeaderValueAbstractions.kproj
	src/Microsoft.AspNet.Mvc.ModelBinding/Microsoft.AspNet.Mvc.ModelBinding.kproj
	src/Microsoft.AspNet.Mvc.ModelBinding/ValueProviders/FormValueProviderFactory.cs
	test/Microsoft.AspNet.Mvc.Core.Test/Microsoft.AspNet.Mvc.Core.Test.kproj
	test/Microsoft.AspNet.Mvc.ModelBinding.Test/Microsoft.AspNet.Mvc.ModelBinding.Test.kproj

Conflicts:
	src/Microsoft.AspNet.Mvc.Core/Formatters/FormattingUtilities.cs
	src/Microsoft.AspNet.Mvc.Core/Formatters/TempInputFormatterProvider.cs
RoslynCompilationService should set the generated code when compilation is successful

Fixes #895
Enabling basic input formatter selection.

Conflicts:
	Mvc.sln
	src/Microsoft.AspNet.Mvc.Core/Formatters/TempInputFormatterProvider.cs
	src/Microsoft.AspNet.Mvc.Core/Microsoft.AspNet.Mvc.Core.kproj
	src/Microsoft.AspNet.Mvc.Core/ReflectedActionInvoker.cs
	src/Microsoft.AspNet.Mvc.Core/ReflectedActionInvokerProvider.cs
	src/Microsoft.AspNet.Mvc/MvcServices.cs
	test/Microsoft.AspNet.Mvc.Core.Test/Microsoft.AspNet.Mvc.Core.Test.kproj
	test/Microsoft.AspNet.Mvc.Core.Test/ReflectedActionInvokerTest.cs

Conflicts:
	src/Microsoft.AspNet.Mvc.Core/Formatters/TempInputFormatterProvider.cs
[Fixes #1035] RouteGroupConstraint should only be added once for non attribute routed actions

1. Changed ReflectedActionDescriptorProvider to add RouteGroupConstraint only once
   for non attribute routed actions.

2. Added tests to cover the scenario.
Clean up `AssociatedMetadataProviderTest`
- remove unused nested class `ModelWithReadOnlyProperty`
- remove unecessary nested classes `RangeAttribute` and `RequiredAttribute`
- use `Assert.NotEmpty()` and `Assert.Single()` where appropriate