Removed the Viewer class and associated functions and exceptions.
Provided empty argument list defaults for InvokeFunction.
Added nicer viewer annotations.
Fixed write attribute access types.
1classA: 2"A class with attribute and method." 3x=123 4defm(self,x): 5self.x=x 6a=A() 7y=A.x 8a.m(321) 9z=a.x