Attach additionalClasses to all custom controls
Attach additionalClasses to all custom controls

Fixes #2489

foosel/OctoPrint,Jaesin/OctoPrint,foosel/OctoPrint,Jaesin/OctoPrint,foosel/OctoPrint,Jaesin/OctoPrint,Jaesin/OctoPrint,foosel/OctoPrint