Upgrade to Ember 1.11-beta.1

HTMLBars goodness! Since there was some breakage and a lot of fiddling
around to get some things working, I took this opportunity to do a big
cleanup of the whole Ember app. I accidentally worked on some new
features too :3

Note that the app is still broken right now, pending on
https://github.com/emberjs/ember.js/issues/10401

Cleanup:
- Restructuring of components
- Consolidation of some stuff into mixins, cleanup of some APIs that
will be public
- Change all instances of .property() / .observes() / .on() to
Ember.computed() / Ember.observer() / Ember.on() respectively (I think
it is more readable)
- More comments
- Start conforming to a code style (2 spaces for indentation)

New features:
- Post hiding/restoring
- Mark individual discussions as read by clicking
- Clicking on a read discussion jumps to the end
- Mark all discussions as read
- Progressively mark the discussion as read as the page is scrolled
- Unordered list post formatting
- Post permalink popup

Demo once that Ember regression is fixed!

ember/app/components/ui/search-input.js

@@ -0,0 +1,36 @@
+import Ember from 'ember';
+
+/**
+  A basic search input. Comes with the ability to be cleared by pressing
+  escape or with a button. Sends an action when enter is pressed.
+ */
+export default Ember.Component.extend({
+  layoutName: 'components/ui/search-input',
+  classNames: ['search-input'],
+  classNameBindings: ['active', 'value:clearable'],
+
+  didInsertElement: function() {
+    this.$('input').on('keydown', 'esc', function(e) {
+      self.clear();
+    });
+
+    var self = this;
+    this.$('.clear').on('mousedown click', function(e) {
+      e.preventDefault();
+    }).on('click', function(e) {
+      self.clear();
+    });
+  },
+
+  clear: function() {
+    this.set('value', '');
+    this.send('search');
+    this.$().find('input').focus();
+  },
+
+  actions: {
+    search: function() {
+      this.get('action')(this.get('value'));
+    }
+  }
+});