feat(rxActionMenu): Action menu cog (originally from Cloud Atlas)

Closes #147
Okay, don't hate me, but maybe bring back the `scope` object now that I know it's needed and use:
```
scope: {
   globalDismiss: '@?'
}
...
if (!_.isBoolean($scope.globalDismiss)) {
    $scope.globalDismiss = true;
}
```