1) all theorems in Orderings can now be given as a parameter
2) new function Theory.defs_of
3) new functions Defs.overloading_info and Defs.is_overloaded
By chapter:
chapters 1 and 2, maybe 3: Peter White
chapters 6, 7 and 8: David von Oheim
chapter 6, maybe 8: Gerwin Klein
chapters 3, maybe 4: Tanja Vos
chapters 1-3 at least: Stefano Bistarelli