support python-3.6 #309

this requires: (#307 (comment) )

• changing:
  • || PYTHON35
  • per || PYTHON35 || PYTHON36
• in:
  • clrmodule/ClrModule.cs
  • src/runtime/converter.cs
  • src/runtime/delegateobject.cs
  • src/runtime/exceptions.cs
  • src/runtime/importhook.cs
  • src/runtime/interop.cs
  • src/runtime/interop35.cs
  • src/runtime/pythonengine.cs
  • src/runtime/runtime.cs
  • src/runtime/typemanager.cs

also a few trick in runtime.cs (see in same comment)
not sure if we need also to generate with a clang a interop36.cs