Data loaders to get genomics data into Glue

Currently includes loaders for :

1. BED (via pyranges)
2. BEDGRAPH (custom tiling)
3. BEDPE (custom tiling)
4. BigWig (via pyranges, but this is slow)
5. RNA-seq and ATAC-seq data matrices and metadata (code is very custom for specific test datafiles)
6. Peak Correlations data (from provided Excel spreadsheet)
7. STL files providing a 3D model downloaded from 3D-GNOME