Overlay / Stacked Icons Support

Is there a way to stack ionicons to make more complex icons? Looking for exact same functionality as fontawesome supports with class= "icon-stack".

Example from fontawesome:

``` html




```


No implementation file, test, or entry point is named. Start by locating how Ionicons are rendered and styled, then compare the requested behavior with the Font Awesome example; done means users can reliably overlay icons with a documented API or class-based approach.

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