v4.2.0

This release adds several significant features: first, we've added a set of taxonomy command-line functionality for combining sourmash gather output with taxonomy databases, and we've also added a new "picklist" feature that enables flexible selection of subsets of databases. Finally, we've added manifests to databases to support picklists as well as faster database loading and signature selection.

As of this release, we've also formally moved development over to the sourmash-bio organization on GitHub, and we've created a new gitter support channel, sourmash-bio/community. Please join us there if you have any questions, comments, or feature requests!

Major new features:

• add tax/taxonomy submodule (#1543, #1628, #1630, #1648)
• add picklists for subsetting databases and results (#1587, #1588, #1623, #1590, #1639)
• Add manifests to support fast Index.select(...) and lazy loading (#1590)

Documentation updates:

• Add new GTDB databases description to docs and start legacy databases page (#1581)
• Change dib-lab/ URLs to new sourmash-bio/ URLs. (#1629)
• Add notice for sustainable open source study (#1580)

Minor new features:

• alias --nucleotide, --no-nucleotide for moltype args. (#1632)
• add signature names to known/unknown hash sigs output by sourmash prefetch (#1646)

Bug fixes and performance improvements:

• Speed up sourmash gather with prefetch by ignoring unidentifiable hashes (#1613)
• Check for MinHash compatibility in MinHash.intersection_and_union(...) (#1627)
• Fix selection w/abund and manifest column type conversions (#1645)

Refactoring and cleanup:

• Fix Rust 1.59 lints (#1600)
• Minor cleanup in sourmash_args & sig submodules (#1586)
• Minor cleanup in minhash module (#1585)
• Fix needless borrows as suggested by clippy (#1636)