docs(native-page-transitions): improve docs

closes #1294

src/@ionic-native/plugins/native-page-transitions/index.ts

@@ -29,21 +29,35 @@ export interface NativeTransitionOptions {
  *
  * ...
  *
- * let options: NativeTransitionOptions = {
- *    direction: 'up',
- *    duration: 500,
- *    slowdownfactor: 3,
- *    slidePixels: 20,
- *    iosdelay: 100,
- *    androiddelay: 150,
- *    winphonedelay: 250,
- *    fixedPixelsTop: 0,
- *    fixedPixelsBottom: 60
- *  };
  *
- * this.nativePageTransitions.slide(options)
+ * // example of adding a transition when a page/modal closes
- *   .then(onSuccess)
+ * ionViewWillLeave() {
- *   .catch(onError);
+ *
+ *  let options: NativeTransitionOptions = {
+ *     direction: 'up',
+ *     duration: 500,
+ *     slowdownfactor: 3,
+ *     slidePixels: 20,
+ *     iosdelay: 100,
+ *     androiddelay: 150,
+ *     fixedPixelsTop: 0,
+ *     fixedPixelsBottom: 60
+ *    };
+ *
+ *  this.nativePageTransitions.slide(options)
+ *    .then(onSuccess)
+ *    .catch(onError);
+ *
+ * }
+ *
+ *
+ * // example of adding a transition when pushing a new page
+ * openPage(page: any) {
+ *
+ *   this.nativePageTransitions.slide(options);
+ *   this.navCtrl.push(page);
+ *
+ * }
  *
  * ```
  */