Remove code 3-year old project about generating invariants
using LA solvers and using them for refinement of predicate analysis.
We still want to work on this in the future,
but the currently existing code is probably not usable
and creates a lot of work when changing things in the util.predicate
package.

git-svn-id: https://svn.sosy-lab.org/software/cpachecker/trunk@13814 4712c6d2-40bb-43ae-aa4b-fec3f1bdfe4c