The ParameterModel and ParameterDescriptor have had a notion of
optionality for a while now, even though all parameters are treated as
'optional' in MVC.
This change removes these settings. Optionality for overloading in webapi
compat shim is reimplemented via a new binder metadata.
This change modifies the default parameter binding behavior for an
ApiController to use the WebAPI rules.
'simple types' default to use route data or query string
'complex types' default to use the body (formatters)
Adds ModelBindingAttribute to enabled model binding
* Modify ReflectedActionInvoker to model bind parameters
* Introduce IBodyReader for reading request bodies
* Introduce types for per-action-context specific binders, value providers
and body readers
Harsh Gupta
Ryan Nowak
Andrew Peters
Pranav K
Yishai Galatzer