Adding a new WebSocket transport to nanomsg.

Signed-off-by: Martin Sustrik <sustrik@250bpm.com>
Making path cross-platform

Signed-off-by: Martin Sustrik <sustrik@250bpm.com>
Updating Autobahn commands after testing on OS X

Signed-off-by: Martin Sustrik <sustrik@250bpm.com>
Sec-WebSocket-Protocol is now set based on socket's SP topology

Signed-off-by: Martin Sustrik <sustrik@250bpm.com>
Ignoring MSVC++ cache files
Simplifying WebSocket stress test
* Refactoring CMSG to store entire cmsg length rather than just data length (for POSIX compliance)
* Now, hdrs field of nn_msg struct is populated in nn_sendmsg()
WebSocket transport now uses updates CMSG API