Partial draft of the new UpdateInfo and maybe datastructure. It is known to be broken while I am figuring out how to do the casts smoothly correctly.
The UpdateInfo should now be working.
Adds the speculativeUpdate to LinearEqualityModule. Lots of misc. changes to support this. Rewrote UpdateInfo class. Added classes Border, BorderHeap and Maybe. Added operator-= to Rational. Currently broken due to UpdateInfo changes.