Adding GIA

This is basically a copy/paste of the existing multiobjective Kodkod parts into Kodkod 2.0. There were changes to the imports and build system to make it compile. These are also the minimum changes copied over to support solving multiobjective optimization problems.

We also removed a bunch of imports/dependencies to external libraries that we don't really need, such as sdg-util.

Reviewers: @cpkleynhans @AtulanZaman @joseph2625