adding readme to dist folder with instructions on where to download stable versions from

[ci-skip]

Author: nfriedly

dist/README.md

@@ -0,0 +1,5 @@
+Note: the latest *stable* release can always be found on [GitHub Releases] 
+or, for browserify users, on [npm]: `npm install --save watson-speech`
+
+[GitHub Releases]: https://github.com/watson-developer-cloud/speech-javascript-sdk/releases
+[npm]: https://www.npmjs.com/package/watson-speech