Merging atomate2 calc_types schema

[mjwen]

Atomate2 is using emmet schema now, but the calc_types schema still exists in both repo: emmet calc_types and atomate2 calc_types.

There are still some stuff not moved from atomate2 calc_types to emmet. For example, the MD option is not in emmet (see here). As a result, atomate2 MD calculations will be assigned a calc_type Unrecognized now.

I guess we want to fully merge these, and then delete the corresponding codes in atomate2, right? Any concerns?

@utf you should have a better idea.

[utf]

Thanks for raising this. We should definitely merge the atomate2 and emmet calc_types. Would you be able to look into that?

[mjwen]

Yes. Will make a PR.