Plan: Create Angular directive

Create an AngularJS directive for dyframe.js.

**Usage:**

``` html
<dyframe df-html="html" df-width="width" df-profile="profile"></dyframe>
```

``` js
angular.module('myApp', ['angularDyframe'])
.controller('MyController', function ($scope) {
  $scope.html = '<html><body>Hello, world!</body></html>';
  $scope.width = 1200;
  $scope.profile = 'smartphone';
});
```
