unit amalgamation

[narudocap]

It might be interesting to look into Henshin units amalgamation. I don't see how to put them together in general, but there must be some notion of compatibility between application strategies that we may explore. Even if no general method, if there are units only in the system being instantiated, by including the units as such in the resulting gts may be useful as a starting point to complete by hand.

[szschaler]

To do this fully, we would probably want a notion of morphisms between units that allows us to create appropriate amalgamations.