Split XHR benchmark code into xhr_benchmark_handler.py

Release note: [XHR benchmark tool] Split XHR benchmark code into xhr_benchmark_handler.py

R=yhirano@chromium.org

Review URL: https://codereview.appspot.com/79420043

git-svn-id: http://pywebsocket.googlecode.com/svn/trunk@792 4ff78f4a-9131-11de-b045-6380ec9940d4
Add a simple handler cookie_wsh.py useful for cookie test

Release note: Add a simple handler cookie_wsh.py useful for cookie test

Review URL: https://codereview.appspot.com/79430043

git-svn-id: http://pywebsocket.googlecode.com/svn/trunk@793 4ff78f4a-9131-11de-b045-6380ec9940d4