v0.9.0:
Bug fixes:
* Allow a broader range of characters in header values. This violates
the RFC, but is apparently required for compatibility with
real-world code, like Google Analytics cookies
* Validate incoming and outgoing request paths for invalid
characters. This prevents a variety of potential security issues
that have affected other HTTP clients.
* Force status codes to be integers, thereby allowing stdlib
HTTPStatus IntEnums to be used when constructing responses
Other changes:
* Make all sentinel values inspectable by IDEs, and split
SEND_BODY_DONE into SEND_BODY, and DONE
* Drop support for Python 3.3.
* LocalProtocolError raised in start_next_cycle now shows states for
more informative errors