Avoid to null out the cookieStore field in doStop(), to prevent random NPEs while stopping.
Improved handling of return values from parser callback, by returning
 as early as possible to avoid race conditions with application code
 that may have returned true and reentered the parsing code.
Fixed tests that broke due to changes in handling of white spaces
between HTTP messages introduced by commit
95c6bad6545604ffa23024ac0092bd9629a520d7.
Added onReadFailure() callback to allow subclasses to perform actions
in case of read failures.
434027 - ReadListener.onError() not invoked in case of read failures.
Simplified code by using request.getAsyncContext().
Fixed content proxying in case of Transfer-Encoding: chunked.
Fixed duplicate Date header issue.