Facility buildings 001 - warehouse

Just a warehouse filled with a lot of crates and a possible flatbed truck in the middle. Added as a 1 x 1 overmap special with low-to-average frequency (0-2). Based on house_rv.json by John-Candlebury.

Question: Is it possible to set which item groups pop up in crates ?
To rotate properly, this should have "overmap":"warehouse_north"