Add js only option to readme

README.md

@@ -45,6 +45,11 @@ It will also create a file called `elm-package.json` which gives a structured
 description of your project. `elm-make` uses this file to figure out what
 directories it needs to look in and which packages are relevant.
 
+If you want to output the compiled javascript only (for instance, if you want to load the javascript from your index.html file) you can do:
+
+```bash
+elm-make --ouput whatever.js Main.elm
+```
 
 ## More Advanced Usage
 
@@ -134,4 +139,4 @@ guidelines.
 If you are in camp #1 creating a package for others, we have plans to help
 automate the process of expanding version bounds. If your project compiles
 with the new stuff and your tests pass, it is conceivable that everything
-just works. We will be experimenting with this!
+just works. We will be experimenting with this!