Update usage command in docs

README.md

@@ -35,7 +35,7 @@ solhint --version
 First initialize a configuration file, if you don't have one:
 
 ```sh
-solhint init-config
+solhint --init
 ```
 
 This will create a `.solhint.json` file with the default rules enabled. Then run Solhint with one or more [Globs](https://en.wikipedia.org/wiki/Glob_(programming)) as arguments. For example, to lint all files inside `contracts` directory, you can do: