[Termtools] [color] unification

[Ulrich Schmidt-Goertz]

Frederic Blanqui schrieb:
> Dear all, it is now possible to use graph approximation based on
> unification in Rainbow and CoLoR (tag <unif> instead of <hde>).
> 
> (To this end, I had to prove the termination, correctness and
> completeness of some unification algorithm.)

Nice. Is this ready to be used in the competition (and if yes, do we
want to use it on such a short notice)?