Improve documentation

Author: djfarrelly

README.md

@@ -1,7 +1,8 @@
 # buffer-static-upload
 
-A straightforward static asset uploader which generates a json file for your
-application to read the uploaded file locations from.
+A straightforward static asset uploader which versions files by their contents
+and generates a json file for your application to read the uploaded file
+locations from.
 
 ## Usage
 
@@ -24,7 +25,17 @@ Usage of buffer-static-upload:
 For example, you can use glob patterns to match multiple sets of files:
 
 ```
-buffer-static-upload -files "public/js/**/*.js,public/css/*.css"
+buffer-static-upload -files "public/js/**/*.js,public/css/*.css" -bucket my-bucket
+```
+
+This will generate a `staticAssets.json` file in this directory like this:
+
+```json
+{
+  "public/css/style.css": "https://my-bucket.s3.amazonaws.com/public/css/style.11985b07e3121564a73d4d6821bfcfe7.css",
+  "public/js/x/another.js": "https://my-bucket.s3.amazonaws.com/public/js/x/another.bfa2d0f60841707efe7be0a94c4caacf.js",
+  "public/js/script.js": "https://my-bucket.s3.amazonaws.com/public/js/script.d55002b60fcfff0b3d355184d23af6f7.js"
+}
 ```
 
 *Note* - The default bucket is used by multiple teams, so if you use that you