Add indeterminate state to section toggles
Add indeterminate state to section toggles

cau-vfu/DMPonline_v4,BibNumUMontreal/DMPonline_v4,cau-vfu/DMPonline_v4,BibNumUMontreal/DMPonline_v4,BibNumUMontreal/DMPonline_v4,cau-vfu/DMPonline_v4,DigitalCurationCentre/DMPonline_v4,DigitalCurationCentre/DMPonline_v4,DigitalCurationCentre/DMPonline_v4