Add demo that uses multiple types of interaction networks

[mpacer]

This is a reason to have vector types as an extension of the vector class so as to allow multigraphs over the same sets of nodes that obey different constraints on the kinds of information transmission that can occur.

Possible examples:

Evolutionary Graph theory: Breaking the symmetry between interaction and replacement

Gender based sexual reproduction restrictions, no gender based behavioral restrictions

Species level reproduction restrictions, alarm calls and communication between species

[DallingerBot]

This issue was moved to Dallinger/Dallinger#58

[DallingerBot]

This issue was moved to Dallinger/Dallinger#59