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.
If we have a criterion as to what qualifies as a specific method and what as the DSL, may be yes but it does not look like there is a clear answer on that. eg: is routing based on method and URI more common or method + URI regex or just method or just method and query parameter. It is a wide spectrum and the usage depends on the usecase. I think if we have a good DSL, it is far easier and intuitive to have a single way of creating these routes.