Update logging section of README

Author: kunalkapadia

README.md

@@ -35,6 +35,22 @@ HTTP_PORT=3000
 npm start or gulp serve (requires gulp to be installed globally)
 ```
 
+## Logging
+
+Universal logging library [winston](https://www.npmjs.com/package/winston) is used for logging. It has support for multiple transports.  A transport is essentially a storage device for your logs. Each instance of a winston logger can have multiple transports configured at different levels. For example, one may want error logs to be stored in a persistent remote location (like a database), but all logs output to the console or a local file. We just log to the console, you can add more transports.
+
+### API logging
+Logs detailed info about each api request to console during development
+![Detailed API logging](https://cloud.githubusercontent.com/assets/4172932/12563354/f0a4b558-c3cf-11e5-9d8c-66f7ca323eac.JPG)]
+
+### Error logging
+Logs stacktrace of error to console
+![Error logging](https://cloud.githubusercontent.com/assets/4172932/12563361/fb9ef108-c3cf-11e5-9a58-3c5c4936ae3e.JPG)]
+
+## Debug messages
+
+Coming soon.
+
 ## Deploy to Heroku
 
 Coming soon.