Caching 112564

The app's production mode currently does not run in rails or passenger setting, so it is typically deployed in development mode. As a result, performance suffers.   This PR aims at improving the app's performance by cleaning up the production mode.  Because the motivation is in performance  area, this PR also made a few adjustments besides making the production mode configuration work.  These adjustments includes invocation of controller cache and use of in-memory data store.  To cut the transmission time for static contents of JS and CSS file, a adjustment is made to enable static content compilation into compressed form at time of deployment.  These improvements yielded almost 500% performance gain in fresh page load (populating browser with empty cache) when tested on local testing environment and 400-500%  gain in page refresh (refresh a already populated page).  Of course, the final observable gain on the hands of real users can vary, depending greatly on distance and speed of his/her internet connection with the server.