This fixes a bug in the mithril TodoMVC application

The bug is caused by lack of keying.

To reproduce the bug:
1. Open the app
2. Create at least two tasks
3. Complete all tasks
4. Go to the completed view
5. uncheck the top item
6. Voilá, see how the first item in the list now has an unchecked checkbox

examples/mithril/js/models/todo.js

@@ -2,9 +2,17 @@
 /*global m */
 var app = app || {};
 
+var uniqueId = (function () {
+	var count = 0;
+	return function () {
+		return ++count;
+	};
+}());
+
 // Todo Model
 app.Todo = function (data) {
 	this.title = m.prop(data.title);
 	this.completed = m.prop(data.completed || false);
 	this.editing = m.prop(data.editing || false);
+	this.key = uniqueId();
 };

examples/mithril/js/views/main-view.js

@@ -51,7 +51,8 @@ app.view = (function () {
 							classes += task.completed() ? 'completed' : '';
 							classes += task.editing() ? ' editing' : '';
 							return classes;
-						})()
+						})(),
+						key: task.key
 						}, [
 							m('.view', [
 								m('input.toggle[type=checkbox]', {

examples/mithril/node_modules/todomvc-common/base.js

@@ -114,7 +114,12 @@
 	})({});
 
 	if (location.hostname === 'todomvc.com') {
-		window._gaq = [['_setAccount','UA-31081062-1'],['_trackPageview']];(function(d,t){var g=d.createElement(t),s=d.getElementsByTagName(t)[0];g.src='//www.google-analytics.com/ga.js';s.parentNode.insertBefore(g,s)}(document,'script'));
+		(function(i,s,o,g,r,a,m){i['GoogleAnalyticsObject']=r;i[r]=i[r]||function(){
+		(i[r].q=i[r].q||[]).push(arguments)},i[r].l=1*new Date();a=s.createElement(o),
+		m=s.getElementsByTagName(o)[0];a.async=1;a.src=g;m.parentNode.insertBefore(a,m)
+		})(window,document,'script','https://www.google-analytics.com/analytics.js','ga');
+		ga('create', 'UA-31081062-1', 'auto');
+		ga('send', 'pageview');
 	}
 	/* jshint ignore:end */
 
@@ -228,7 +233,7 @@
 			xhr.onload = function (e) {
 				var parsedResponse = JSON.parse(e.target.responseText);
 				if (parsedResponse instanceof Array) {
-					var count = parsedResponse.length
+					var count = parsedResponse.length;
 					if (count !== 0) {
 						issueLink.innerHTML = 'This app has ' + count + ' open issues';
 						document.getElementById('issue-count').style.display = 'inline';

examples/mithril/package.json

 {
   "private": true,
   "dependencies": {
-    "mithril": "^0.1.20",
     "todomvc-common": "^1.0.1",
-    "todomvc-app-css": "^1.0.1"
+    "todomvc-app-css": "^1.0.1",
+    "mithril": "~0.2.0"
   }
 }