Added new 'BaseView' that all views inherit from.

Added Google Analytics, which now tracks page views & many events. See 'index.html' for uncaught error tracking, 'js/views/app.js' for event tracking & 'js/router.js' for pageview tracking. Uses a different tracking code for dev & prod.

Added "release" methods to views, called when cleaning up. Most views just use the method they inherit from the new 'BaseView'. Also extended Vm with better view tear-down.

"Top Rated" / "Recently Added" tabs on landing page are now functional.

Fixed some bugs: added some missing method binding to views/landing/page.js; fixed problem with adding the first tag to a plugin.

"Favorite" can now be toggled from "Tag" pages.