added proof reconstructon for Z3,
added certificates for simpler re-checking of proofs (no need to invoke external solvers),
added examples and certificates for all examples,
removed Unsynchronized.ref (in smt_normalize.ML)
(benchmark Isabelle
:extrafuns (
(uf_2 Real)
(uf_1 Real)
)
:assumption (< (+ (* 3.0 uf_1) (* 7.0 uf_2)) 4.0)
:assumption (< 3.0 (* 2.0 uf_1))
:assumption (not (< uf_2 0.0))
:formula true
)