Added a new notification to RefinementObserver for repartitionings.  Reworked MeshTransferFunction to use this instead of didHRefine.  Now passes a simple test against refinements.  Also, fixed an issue in Mesh where it could call didHRefine with a set of cellIDs not all of which had yet been refined.
Made some didHRefine notifications, which had been done one cell at a time, execute for the whole set of cells which are being h-refined.
Made basisCacheForCell call getElementType instead of getElement()->elementType() (which is less efficient, and which will fail for elements that are no longer active).
Added test against RefinementPattern::mapRefCellPointsToAncestor(), and fixed the bug revealed by it.
Added new tests against MeshTransferFunction and fixed some bugs.