Change --url to --base in README

README.md

@@ -54,9 +54,9 @@ See `readable --help` for more information.
 
 **Download a web page using [cURL](https://en.wikipedia.org/wiki/CURL), parse it and save it into a file:**
 
-`curl https://github.com/mozilla/readability | readable --url=https://github.com/mozilla/readability > example.html`
+`curl https://github.com/mozilla/readability | readable --base=https://github.com/mozilla/readability > example.html`
 
-It's a good idea to supply the --url parameter when piping input, otherwise `readable` won't know the document's URL, and things like relative links won't work.
+It's a good idea to supply the --base parameter when piping input, otherwise `readable` won't know the document's URL, and things like relative links won't work.
 
 ### Why Node.js? It's so slow!