Python function annotations containing C/C++ types are no longer
generated when using the -py3 option. Function annotations support
has been moved to a feature to provide finer grained control.
It can be turned on globally by adding:
%feature("python:annotations", "c");
or by using the command line argument:
-features python:annotations=c
The implementation is designed to be expandable to support different
annotations implementations. Future implementations could implement
something like the following for generating pure Python types:
%feature("python:annotations", "python");
or typing module types to conform to PEP-484:
%feature("python:annotations", "typing");
Closes#1561
Issue #735
