Convert the documentation to Asciidoc

A few small revisions were made, and Erlang.mk has been updated.

doc/src/manual/cowboy_router.asciidoc

@@ -0,0 +1,56 @@
+= cowboy_router(3)
+
+== Name
+
+cowboy_router - router middleware
+
+== Description
+
+The `cowboy_router` middleware maps the requested host and
+path to the handler to be used for processing the request.
+It uses the dispatch rules compiled from the routes given
+to the `compile/1` function for this purpose. It adds the
+handler name and options to the environment as the values
+`handler` and `handler_opts` respectively.
+
+=== Environment input
+
+dispatch = dispatch_rules():: Dispatch table.
+
+=== Environment output
+
+handler = module():: Handler module.
+handler_opts = any():: Handler options.
+
+== Types
+
+=== bindings() = [{atom(), binary()}]
+
+List of bindings found during routing.
+
+=== dispatch_rules() - opaque to the user
+
+Rules for dispatching request used by Cowboy.
+
+=== routes() = [{Host, Paths} | {Host, cowboy:fields(), Paths}]
+
+With types:
+
+* Host = Path = '_' | iodata()
+* Paths = [{Path, Handler, Opts} | {Path, cowboy:fields(), Handler, HandlerOpts}]
+* Handler = module()
+* HandlerOpts = any()
+
+Human readable list of routes mapping hosts and paths to handlers.
+
+The syntax for routes is defined in the user guide.
+
+=== tokens() = [binary()]
+
+List of host_info and path_info tokens found during routing.
+
+== Exports
+
+=== compile(routes()) -> dispatch_rules()
+
+Compile the routes for use by Cowboy.