Add permessage-deflate support.

Review URL: https://codereview.appspot.com/8666044

git-svn-id: http://pywebsocket.googlecode.com/svn/trunk@752 4ff78f4a-9131-11de-b045-6380ec9940d4
Rename extension processor classes to match extension identifier.

Bonus: Remove commented out x-webkit prefixed extension registration code 
    which now are never going to live.

Review URL: https://codereview.appspot.com/8576046

git-svn-id: http://pywebsocket.googlecode.com/svn/trunk@753 4ff78f4a-9131-11de-b045-6380ec9940d4
Add permessage-deflate tests on two-message cases.

Review URL: https://codereview.appspot.com/8537044

git-svn-id: http://pywebsocket.googlecode.com/svn/trunk@754 4ff78f4a-9131-11de-b045-6380ec9940d4
Split EndToEndTest into smaller classes

After this, I'm going to shorten test methods.

Release note: n/a (test only change)

Review URL: https://codereview.appspot.com/8792043

git-svn-id: http://pywebsocket.googlecode.com/svn/trunk@755 4ff78f4a-9131-11de-b045-6380ec9940d4