Listener Options

[lmajano]

@denuno What would be the best way to configure the listener options available in undertow: http://undertow.io/undertow-docs/undertow-docs-1.3.0/listeners.html

[denuno]

The only listener we didn't have was HTTP2, which I wanted to get in there, so the first implementation is in, along with a LearningPushHandler, which theoretically builds up a cache of things the server sends out over http and then can send it out over http2 if the browser supports it. Seems pretty darn cool but I haven't tested it much. Enabled by passing -http2 true or --http2-enable true. HTTP2 basically requires SSL so that's automatically enabled if http2 is.