Closes#1318
BREAKING CHANGE: $ionicActionSheet's default behavior is now to cancel
when the app's state changes. To disable this behavior, pass
`cancelOnStateChange: false` into $ionicActionSheet.show().
BREAKING CHANGE: $ionicActionSheet now returns a method to hide the
action sheet.
Previously, it returned an object that had a `show` and `hide` method.
This was undocumented, but if you used it, here is how to migrate your
code:
Change your code from this:
```js
var sheet = $ionicActionSheet.show({...});
sheet.hide();
```
To this:
```js
var hideSheet = $ionicActionSheet.show({...});
hideSheet();
```
Closes#1369.
Right now `buttonClicked` accepts only the index of the pressed button that means you have to work with indices to decide which one it is. In case you move buttons around to get better UX, you'd have to be very careful with those indices. It's easier to add `id` property to buttons and simply check for it. Index-agnostic solution is more maintainable and leads to less changes to the code when the buttons order is being changed.