(bug 54319) Show diff when order of snaks changed

This needs Ie60368122fd1db5b1d80107ab017be0686dfd05e in Diff

Change-Id: I82b84e866ed3bc2aac037219b25e11a231728e20
Use ComparableComparer for ClaimDiffer construction

Change-Id: Ida96663d24bcf3250dbbe9dae5aebf4453350e8d