Migrate acsets core to new standalone package

[epatters]

Migrate acsets core to new standalone package

[mehalter]

We have SubACSets in AlgebraicPetri currently that needs to be moved. The main thing is the functionality for calculating most common ACSet. Do you think that will get migrated to the new ACSets package or still into somewhere in Catlab?

[epatters]

I'm expecting the subacsets functionality to remain in Catlab because it uses interfaces for lattices provided by Catlab.Theories. It would be great to upstream most-common-subacset to Catlab at some point.

[mehalter]

Ok cool that's exactly what I was thinking. I'll get a PR to migrate that over for the 0.15 release. It would be good to coincide that with AlgebraicPetri since it's removal will be a breaking change on that end. @epatters do you have a goal date for that release? Just so I have a due date in mind?

[epatters]

My hope and goal is to have this done by the end of the week.

[mehalter]

Ok awesome, I'll follow suit and get a PR together for SubACSets MCA stuff as well by the end of the week for the release