refactor(demos): give each component section its own view

demos/component-docs/popups/popups.ts

@@ -0,0 +1,16 @@
+import {IonicPlatform, IonicView, Popup} from 'ionic/ionic';
+
+@IonicView({
+    templateUrl: 'popups/popups.html',
+})
+export class PopupsPage {
+
+  constructor(popup: Popup) {
+    this.popup = popup;
+  }
+
+  showPopup() {
+    this.popup.alert("Popup Title").then(() => {
+    });
+  }
+}