Comment 4 for bug 882315

Damn it, scanned:

    cls.add_method('get_len',
                   'std::size_t',
                   [],
                   is_const=True, custom_name='__len__')

manually written:

    VectorLike.add_method('get_len', 'size_t', [], custom_name='__len__')

pybindgen doesn't know std::size_t, only size_t. I just need to add an alias std::size_t = size_t to pybindgen type handlers. Trivial fix.