removed "extended" library and fixed some build issues
Merge branch 'master' into dev
.ocamlinit
improve arith handling in hysteresis
todo
simpler NNF, with polarity-dependent elimination of equivalence
done right
additional functions in DBEnv
prepare for renaming in CNF
De Bruijn manipulations in Formulas and ScopedTerms
progress in formula renaming, with a cleaner interface in Skolem and some more code in Cnf
definitional CNF implemented, based on an estimation of the number
of clauses implemented with dynamic programming.
merge from branch better_cnf
more functions in DBEnv
remove De Bruijn indices in proxy definitions in CNF
merge bugfix from "better_cnf"
Merge branch 'dev' back to master (bugfix and better CNF)