Add Weierstrass elliptic functions.
Integration improvement.
Add '$tryRecompileArguments' flag.
Split integrals involving multiple square roots.
Add polylog.
Replace strings by symbols.
Misc cleanups, merge ggreater.lisp into macros.lisp.
Rename PolynomialIdeals to PolynomialIdeal
Add derivatives of Airy functions and Lambert W.
make ATANFLAG into a union type and correct bug (typo) in fs2expxp.