Add height from OSM `height` and `min_height` tags

The building height can be parsed using the number of stories from building:levels as H:x or HBEX:x, but also using height from height or min_height as HHT:x.

\fyi @ds @pdlmora

assigned to @laurens

changed the description

created branch 16-add-height-from-osm-height-and-min_height-tags to address this issue

mentioned in merge request !13 (merged)

closed with merge request !13 (merged)