Add a web server example

Explore re-routing in middleware.

examples/web_server/README.md

@@ -0,0 +1,27 @@
+Cowboy Static File Handler with Index Support
+=============================================
+
+To compile this example you need rebar in your PATH.
+
+Type the following command:
+```
+$ rebar get-deps compile
+```
+
+You can then start the Erlang node with the following command:
+```
+./start.sh
+```
+
+Cowboy will serve all the files you put in the priv/ directory. You can replace
+the filename given in the example URL with the one of a file you added to this
+directory to receive that file. A middleware has been added that will re-route
+the request to a different handler if the requested path is a directory.
+
+Example
+-------
+
+Point your browser to http://localhost:8080 to see the contents of `priv/`. You
+can click on a link to see that file. If HTML is not preferred, the contents of
+a directory will be listed as a JSON array (e.g. with `curl
+http://localhost:8080`).