The directorin typemaps in the director methods now use std::move on the
input parameter when copying the object from the stack to the heap prior
to the callback into the target language, thereby taking advantage of
move semantics if available.
Use SwigInterface as a suffix to the class name when naming the
interface class instead of using a simple I as a prefix.
%feature_custom can be used to use I as a prefix if so desired.
