cleanup task: add or fix building heights

[wilsaj]

We have pre-existing OSM buildings that will be missing their heights, and we also need to fix wonky heights from the initial import (example: 3.43999999999999)

should be easy to do both by conflating with nodes that intersect and have the correct height values

[maxerickson]

I put a script to fix the existing heights here: https://github.com/maxerickson/osm-round-austin

I haven't uploaded the result because I haven't decided if I think it would be a separate mechanical edit from the initial import. I've also only done a cursory check that it works correctly.

[wilsaj]

Nice - thanks so much for putting that together! I'll let you make your own decision, but as far as I'm concerned I think fixing our screw-up falls under the same umbrella. Is there anything I can do to help?