backbone_marionette_require code style.

(#572)

I went through the Backbone + Marionette + Require app, and...

- Updated the code style
- Added in missing spec features:
  - cancel edit on escape
  - save edit on blur
  - cursor at end of input on dblclick
  - "Clear completed" button was always showing, and without a "(3)" counter
  - grammar: 0 items left, 1 item left, 2 items left
- Switched all but one dependency to Bower
  - [requirejs-tpl](https://github.com/ZeeAgency/requirejs-tpl) isn't registered
- Removed .jshintignore as most files are now out of the `lib` folder, and in the `bower_components` directory
- Consolidated to one index.html file. There were two index files. index-dev for non-compiled, index for a script that ran through the RequireJS optimizer. I thought it would be better if there was only one index.html, which, like all the other examples, serves non-uglified code. I kept the optimizer build file in, and removed the out of date build files
- Assigned `app` to `window.app` to make use of `app.vent`
  - Previously, the `Footer` was being created and configured before an `app` module was accessible. By putting `app` in the global scope, I was able to use the `app.vent` method from within `js/views/Footer.js` without requiring access to the `app` module 

I have a question to anyone more familiar with these tools. In `js/views/CompletedCount.js`:

```js
/*global define */

define([
	'marionette',
	'jquery'
], function (Marionette, $) {
	'use strict';

	return Marionette.View.extend({
		initialize: function () {
			this.listenTo(this.collection, 'all', this.render, this);
		},

		render: function () {
			/**
			 *
			 * Can anyone recommend a better way of having this M.View
			 * represent just one element from a region?
			 *
			 * I tried setting an `el` property on the View to `#clear-completed`,
			 * but it didn't end up returning an element.
			 *
			 */
			this.$el = $('#clear-completed');

			var completedTodos = this.collection.getCompleted();

			this.$el
				.toggle(completedTodos.length > 0)
				.html('Clear completed (' + completedTodos.length + ')');
		}
	});
});
```

@jsoverson, as you were the original author of this app, would you mind giving a quick look over the changes, making sure this is still a good representation of Marionette with RequireJS?

And to everyone, if you can think of more ideal solutions than the ones I've implemented, please let me know.

Thanks!