reintroduced code that keeps track of whether the Isabelle and Metis proofs are in sync -- generalized to work with the new skolemizer
no_document use_thy "Setup";
use_thy "Introduction";
use_thy "Foundations";
use_thy "Refinement";
use_thy "Inductive_Predicate";
use_thy "Evaluation";
use_thy "Adaptation";
use_thy "Further";