Comprehensive HTTP Router

Here is a partial solution to Issue #202, at least for different HTTP methods.  There is no provision for websocket or SSE support here.  This is more or less a port of the excellent Vert.x RouteMatcher for RxNetty.  I do want to point out that I had to force queryParameters to be mutable on HttpRequest for this particular implementation.
The lists could be turned into a Multimap by method if you wish, at the expense of extra code complexity.  I can change it if you like.  The point is that the same URI binding could exist across multiple HTTP methods.