Allow only a group to be exported.
Allow only a group to be exported.

Implements the request in #84, though I'm unsure if placement as
submenu items are the best UX.

EvNaverniouk/doby-grid,globexdesigns/doby-grid,RobertoMalatesta/doby-grid,EvNaverniouk/doby-grid,globexdesigns/doby-grid,RobertoMalatesta/doby-grid