deprecate board

BUR #19924 has been approved by @evazion.

deprecate board

Ambiguous with chalkboard whiteboard bulletin_board wooden_floor and others.

BUR #19925 has been approved by @evazion.

create alias markerboard -> whiteboard

utility alias

The bulk update request #19925 (forum #254164) has been approved by @evazion.

The bulk update request #19924 (forum #254163) has been approved by @evazion.