when a Uri is expected, validate it and populate it
when a Uri is expected, validate it and populate it

ndevenish/simple-json,facebook-csharp-sdk/simple-json,jasonmead/simple-json,facebook-csharp-sdk/simple-json,suaff/simple-json,suaff/simple-json,ndevenish/simple-json,suaff/simple-json,jasonmead/simple-json,jasonmead/simple-json,ndevenish/simple-json,facebook-csharp-sdk/simple-json