refactor(demos): make each button section a module

demos/component-docs/buttons/sizes/pages.ts

@@ -0,0 +1,13 @@
+import {Page} from 'ionic/ionic';
+import {forwardRef} from 'angular2/angular2';
+import {AndroidAttribute} from '../../helpers';
+
+@Page({
+  templateUrl: 'buttons/sizes.html',
+  directives: [forwardRef(() => AndroidAttribute)]
+})
+export class SizesPage {
+    constructor() {
+
+    }
+}