Allow spanned icons to be styled separately
The ability to add icons via text (i.e. `{faw-android}`) is awesome, but since the spanned font inherits the style of the rest of the text it is quite hard to use in practice.

It would be nice to allow the user to use a separate theme or style for the icon so that it can be sized/colored separately from the normal text, making it much more practical to use this feature.

This SO comments lists three practical ways in which this can be implemented: https://stackoverflow.com/a/20861064/332798. `TextAppearanceSpan` is likely the best way for Iconics.