Move/move conflict detection is non-deterministic

[slarse]

Because in a move/move conflict, each PCS containing the moved node will conflict with two other PCSes (base and left, base and right or left and right). The problem is that the PCSes from the left and right revisions that conflict with each other will conflict with two different PCSes from the base revision. If these base revision PCSes are removed during merging, then the PCSes from left and right will never be found to conflict.

I will put a more detailed explanation in the thesis.

The quick fix for this is to modify getOtherX to return all conflicting PCSes of that type.