allow the angio suffix for func data

[Proulx-S]

functional MRA is becoming a thing. Unless I'm mistaken, the angio suffix is only allowed for anat data. For my single-vessel fMRI (fMRA), I'm stuck using the inappropriate bold suffix--at least that is the least wrong suffix out of the choices BIDScoin allow (I'm presuming BIDScoin is right here).

To me, the simplest would be to allow the angio suffix for func data.

Thanks for your attention and
Keep up the good work!
Sébastien