Fix bug in ContentLengthFilter and Util.pump.

Allow the underlying AsyncSocket to cache pending data for pause/resume.
AsyncHttpServer: Add support for HEAD method on assets.
Add FutureRunnable and FutureThread.
Add HandlerFutureCallback to manage a callback onto a Handler thread.
AsyncServer: make the executor stuff private.
Input/Output stream emitter/sink: stop using the executors. Remove broken blocking support.
Util.emitAllData: watch for emitter pause.
AsyncHttpServer enhancements:
Custom body parsers.
Get local socket server on listen.
v121
Merge branch 'koush-authority/master'
iml
iml garbaje