make http.client.HTTPResponse concrete in 3.4 (#2244)
make http.client.HTTPResponse concrete in 3.4 (#2244)

Matches the implementation in https://github.com/python/cpython/blob/3.4/Lib/http/client.py#L308

The ignore works around python/mypy#5027 (commented further up in the 3.5 branch).

Part of #1476.
euresti/typeshed