Merge pull request #498 from minrk/json-kwargs

support json kwargs on send/recv_json
regen platform.hpp

on:

- OS X 10.9
- FreeBSD 10
- Fedora 15
Merge pull request #499 from minrk/platforms

regen platform.hpp
changelog
authors
bump version to 14.1.0
back to dev
remove pip message from setup.py
update readme
write compiler config to build_lib

To ensure that the latest version is actually what is installed.

previously, `setup.py build` would have to be run twice to ensure the files are in the right place.

fixes `pip install pyzmq` on PyPy
Merge pull request #501 from minrk/build_lib_config

write compiler config to build_lib
Allow Context to be used as a context manager
Merge Pull Request #503 from funkybob/context-managers

Make Context a ContextManager