Merge pull request #25 from sgalaburda/master

Thanks, the fix looks good. I forgot to port notify_on_close to linux during the process.
add coro.asn1.ber and coro.ldap.query modules
split _ldap.pyx into coro.asn1.ber and coro.ldap.query
pxd file for _coro.pyx
pxd file for socket.pyx
modernize pyrex -> cython
parse_address(): split into 3 functions (in preparation for support for linux raw sockets)
modernize pyrex -> cython
pull compile-time-env variables out, they are now set in setup.py
modernize pyrex -> cython
modernize pyrex -> cython
modernize pyrex -> cython
modernize pyrex -> cython
modernize pyrex -> cython
set compile_time_env here rather than in _coro.pyx
various neatenings
modernize pyrex -> cython
http_file.read(): implement size argument
several problems with file_handler fixed
Replaced most of the README with the front end of the tutorial.
The previous content was confusing, outdated, and unhelpful.
direct link to the tutorial
HTTP_Protocol_Error: derive from Exception
HTTP_Upgrade: new exception
HTTP_Upgrade: allow a handler to upgrade out of HTTP