Remove the JsonpFormatter as it has been moved to its own project.
Remove the JsonpFormatter as it has been moved to its own project.

WebApiContrib/WebAPIContrib,yonglehou/WebAPIContrib,modulexcite/WebAPIContrib,andyshao/WebAPIContrib,TerraVenil/WebAPIContrib,yonglehou/WebAPIContrib,TerraVenil/WebAPIContrib,WebApiContrib/WebAPIContrib,modulexcite/WebAPIContrib,andyshao/WebAPIContrib