Integrate with multi-infrastructure implementation of InfrastructureModels.jl

[rb004f]

[rb004f]

• [ ] new data format for explicit linkage data
• [ ] new infrastructure key in data, ref, cons, vars, etc
• [ ] resolve how to dispatch on formulation type when constitute infrastructure models are unified in a single data/ref/con/vars
• [ ] update documentation to reflect new ways of coupling things (parsing, internal data structures, etc.)