Add support for fields when deserializing strongly-typed objects

[yaakov-h]

Not just properties.

This will require some abstraction over both.

[yaakov-h]

Thinking out loud here:

This will require some level of abstraction. Probably the IPropertyMapper shouldn't return a string or PropertyInfo or what have you, but instead some abstraction layer over an (object, PropertyInfo) or (object, FieldInfo) tupl.

[yaakov-h]

We already have this abstraction now through IObjectReflection/IObjectMember. Implementing this should now be trivial.

[yaakov-h]

We now have this in place but only for System.ValueTuple<...> types so far.