Orbit height not set on accordion

Orbit slider container height is not being calculated, when Orbit slider is not visible (when inside closed accordion).

Orbit's container height normally is being calculated from the largest image/element in it. But, if the container is not being displayed, it can not calculate the height, because jQuery can't calculate image height, if parent element is not displayed ```display: none```... It is how it its.

In the code ( https://github.com/zurb/foundation/blob/master/js/foundation/foundation.orbit.js#L266 ) there I see those lines:
```javascript
$(window).on('resize', self.compute_dimensions);
$(window).on('load', self.compute_dimensions);
```

If somehow you could trigger ```compute_dimensions``` after opening an accordion's tab... For example, you could trigger ```accordionOpened``` event or something and bind Orbit to listen the event... At least give me a direct access to ```compute_dimensions``` !

Currently I fixed this problem by calling
```javascript
$(window).resize();
```
on accordion's tab click.