unconceal symbols stemming from inductive_set specifications, which are regular part of user-space specification;
also unconceal corresponding primitive definitions, which are official conversions between predicates and sets
src/Pure
src/FOL
src/HOL
src/ZF
src/CCL
src/CTT
src/Cube
src/FOLP
src/LCF
src/Sequents
src/Doc
src/Tools