Tweaked commented-out line that outputs stiffness matrix for debugging purposes, to announce that that's what it's doing, and to be compatible with my refactor of a couple months ago.
Added test cases to GDAMinimumRuleTests, and fixed the bugs revealed by these in BasisReconciliation and GDAMinimumRule:
BasisReconciliation: fixed the way coarse domain points are computed.  (They were flipped, which happened to work so long as we only had 1-irregular meshes.)
GDAMinimumRule: fixed a couple issues with the way dof ownership works.  Most egregiously, on some meshes, could have double-claimed global dof indices, ultimately resulting in zero rows and columns for spurious global dofs.