Also, update nova-novncproxy to import websockify instead of wsproxy.

Add wswrapper info to utils/README.md and docs/TODO. Remove innacurate
info from docs/notes.

Looks like disabling web-socket-js debug messages by default that we
get a minor speedup.

Python proxy should support both 75 and 76 (00) modes. Also, update ws
test to more reliably hit the WebSockets ordering/drop issue.

The purpose of the code is to be incorporated into other web projects
(whether those are free or not). AGPL prevents combination with other
HTML and javascript that is under a weaker (or proprietary) license.
Better would be a lesser AGPL, but there is not GNU standard for that.
So LGPL-3 meets most of my requirements. If somebody modifies the
actual client code and conveys it, then they must release the changes
under LGPL-3 also.

Add some implementation notes in docs/notes.