GRCh37 → GRCh38 Converion

The repo is still private for now, but this morning I got right to it.

I had been building a 38 → 37 liftover downgrade for my local GWAS Association DuckDB. However I realized it would probably be much easier to upgrade the input genotype to 38, as both the GWAS and Reference Panel set in Google public genetic dataset are GRCh38.

So I was able to nuke all the things.

I also updated the spec to grab BQ data from Google, and to create reference stats on the fly and upload. Should be ready to implement now.