Putting crates in a subdirectory

[nleroy917]

We have a lot of crates now:

With more on the way:

• gtars-scatrs
• gtars-genomicdist

I wonder if we should adopt the pattern of having a crates folder where all of these live.

[nsheff]

Related: I am wondering if we should think about rudcing the number of crates; does it make sense for any of these to be combined?

Setting aside the non-feature crates like cli and core, and bindings crates like python, r, wasm, which are fixed -- I think it's reasonable to try to have no more than 8-12 crates, but I'm worried we're making crates for things where there are just a few functions/commands, then it could get out of hand...

[nleroy917]

yeah i think fragment splitting doesnt need to be its own thing. A lot of other stuff though feels pretty independent... maybe scoring can get consumed into overlaprs