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();
```
Main changes:
* Use gulpfile now (build was getting way too disorganized with custom
tasks; gulpfiles are much easier to build clean custom tasks with than
Grunt.
* View README#Development for updated commands
* Docs written for ionContent, ionHeaderBar, ionInfiniteScroll.
* Docs are pushed to ajoslin's fork of ionic-site until they reach a
* point where they can be published.
**TODO, In Order of Priority**
1. Finish writing source-documentation for all existing components
2. Add multiple versions of docs (one per release & nightly, latest
stable release docs being shown by default)
3. Add examples generation
4. Add searchbar to docs
