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 also comes with a rename of the namespace
Microsoft.AspNet.Mvc.ApplicationModel to
Microsoft.AspNet.Mvc.ApplicationModels.
Also tuned up some parameter and variable names for increased
understandability.
sornaks
Ajay Bhargav Baaskaran
Ryan Nowak