Renamed WebSocketTransport to JettyWebSocketTransport, in preparation of the JSR 356 implementation.
Updated versions of Jetty (to 7.1.12), Dojo (to 1.9.0),
jQuery (to 1.10.2) and other libraries and Maven plugins.
Fixes COMETD-449 (WebSocket protocol cannot be configured in
JavaScript client).

Added configuration option "protocol".
Wired JSR 356 implementation.
Implemented Servlet 3.1 async I/O transport, and improved WebSocket implementation.
Improvement that follows COMETD-453: in case the transport can't be
negotiated, log and throw an exception.
Merged branch '2.7.x' into 'master'.
Merged branch '2.7.x' into 'master'.
Code changes to make tests pass: core code fixes and test code fixes.