Add usage information

Author: AdamMajer

README.md

@@ -4,3 +4,26 @@ Certain build environments like the [Open Build Service](https://build.opensuse.
 * it reads NPM published tarballs and presents them on a localhost interface
 * it runs `npm install`
 
+- [Installation](#installation)
+	- [From Release](#from-release)
+	- [From Git](#from-git)
+- [Usage](#usage)
+
+# Installation
+
+## From Release
+`npm install --production`
+
+## From Git
+`npm install`
+`npm run build`
+
+At this point the application is in `dist/` and can be used as from a tagged released version
+
+# Usage
+
+From the directory of an application where you want to run `npm install`,
+
+	NPM_TGZ=list of all NPM tgz tarballs or directory containing them
+	node ${path_to_this_app}/dist ${NPM_TGZ} ${npm install parameters}
+