Update README.md

Author: fquirin

README.md

@@ -21,3 +21,6 @@ reverseProxy.start();
 Be sure to check-out the source to tweak the number of possible threads for more performance.  
 
 Good to know: Thanks to Undertow it also works as proxy for WebSocket servers out-of-the-box :-)
+
+### To-do
+Introduce a config-file and maybe some command-line options to handle custom path-to-target mappings.