Add logger feature

README.md

@@ -25,6 +25,7 @@ proxy is `localhost:8080`, which is the default one in our example.
 - Use a `custom http.Transport` to perform requests to the target server
 - You can specify a `MITM certificates cache`, to reuse them later for other requests to the same host, thus saving CPU. Not enabled by default, but you should use it in production!
 - Redirect normal HTTP traffic to a `custom handler`, when the target is a `relative path` (e.g. `/ping`)
+- You can choose the logger to use, by implementing the `Logger` interface
 
 ## Proxy modes
 1. Regular HTTP proxy