Support groups in components with options

[atmgrifter00]

😯 Problem to Solve

We have clients that are having to provide workarounds, or a non-ideal UX for select/combobox dropdowns where the options are categorized under a named group (see this PR as an example, and for discussion around the issues).

💁 Proposed Solution

FAST has a similar issue already filed, though as written it is addressing the FASTListbox (however, I've already commented on if that issue should apply to FASTSelect and FASTCombobox as well), which outlines an implementation strategy.

One thing not discussed directly in the FAST issue that has some importance to us (based on client request) is the display of the group in the selected item display (not just in the dropdown area). As we now have a forked template for the dropdown components we have the freedom to update the display area as needed. However, it would be good to have UX input on this before we solidify an implementation strategy.

Before starting implementation, an HLD should be created.

[atmgrifter00]

Closed, as this is a dupe of #791.