New macro added to the family of %interface macros. This new macro
is for adding additional interfaces for the generated interface to
extend/derive from.
Closes#1188
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.
William S Fulton