Double Portcullis Converted to Blender 2.81

With the Blender 2.80 major update some backwards compatibility was lost. This is something software developers avoid as much as possible, but to truly move forward sometimes it is necessary. Thus I am converting models from 2.7 to 2.8.

This involves lots of reorganizing as the old layer/group system has been replaced by Collections. The vast majority of things translate perfectly to 2.8 as demonstrated by this rather complicated model using numerous drivers and constraints.