421697 - IteratingCallback improvements

Cleanup WebSocket impl first

+ Logic for size on Generator was backwards.
+ Logic in Generator for RSV flags was incorrect.
+ Generalizing flagsInUse for Parser too
421697 - IteratingCallback improvements

avoid wrapping writeCallback
Idle state added to IteratingCallback for SPDY
421697 - IteratingCallback improvements

Use the iteratingcallback for websocket
use gather writes for websocket
always write entire websocket payload
Merge branch 'master' of ssh://git.eclipse.org/gitroot/jetty/org.eclipse.jetty.project
421697 - IteratingCallback improvements

made gather size configurable
Merge branch 'master' of ssh://git.eclipse.org/gitroot/jetty/org.eclipse.jetty.project