v0.4.0 for UE 4.13

-Added SIOJson for Blueprint Json construction and conversion, based on VaRest
-Auto-conversion for nodes
-Blueprint callbacks and events bound to functions references by function name
-Conversion of JsonObjects to and from UStructs, including Blueprint UStructs with automatically trimmed long names into readable short names
-Overloaded EmitNative for all expect UE native data types
-Much simplified C++ usage based on FJsonValue and FJsonObject