Create classes for the different symmetry classes of plane partitions (Cyclically symmetric, Totally Symmetric, etc.), along with methods taking elements in these symmetry classes to an object in a fundamental domain (usually an order ideal in some associated poset).

CC: @jessicapalencia @tscrim @mantepse

Component: combinatorics

Keywords: days99, IMA Coding Sprint

Author: Kevin Dilks, Spencer Cook, Jessica Striker

Branch/Commit: public/combinat/symmetry_classes_plane_partitions-28244 @ a3c1c58

Reviewer: Travis Scrimshaw

Issue created by migration from https://trac.sagemath.org/ticket/28244