Webpack (#1367)

* Replace gulp with webpack and npm scripts for JS compilation
* Set up Travis CI to commit compiled JS
* Restructure `js` directory; only one instance of npm, forum/admin are "submodules"
* Refactor JS initializers into Application subclasses
* Maintain partial compatibility API (importing from absolute paths) for extensions
* Remove minification responsibility from PHP asset compiler
* Restructure `less` directory

js/src/forum/components/PostEdited.js

@@ -0,0 +1,44 @@
+import Component from '../../common/Component';
+import humanTime from '../../common/utils/humanTime';
+import extractText from '../../common/utils/extractText';
+
+/**
+ * The `PostEdited` component displays information about when and by whom a post
+ * was edited.
+ *
+ * ### Props
+ *
+ * - `post`
+ */
+export default class PostEdited extends Component {
+  init() {
+    this.shouldUpdateTooltip = false;
+    this.oldEditedInfo = null;
+  }
+
+  view() {
+    const post = this.props.post;
+    const editUser = post.editUser();
+    const editedInfo = extractText(app.translator.trans(
+      'core.forum.post.edited_tooltip',
+      {user: editUser, ago: humanTime(post.editTime())}
+    ));
+    if (editedInfo !== this.oldEditedInfo) {
+      this.shouldUpdateTooltip = true;
+      this.oldEditedInfo = editedInfo;
+    }
+
+    return (
+      <span className="PostEdited" title={editedInfo}>
+        {app.translator.trans('core.forum.post.edited_text')}
+      </span>
+    );
+  }
+
+  config(isInitialized) {
+    if (this.shouldUpdateTooltip) {
+      this.$().tooltip('destroy').tooltip();
+      this.shouldUpdateTooltip = false;
+    }
+  }
+}