bring over CpdtTactics.v from jitk as well (de-compcert-ified)
bring over CpdtTactics.v from jitk as well (de-compcert-ified)

mit-pdos/fscq-impl,mit-pdos/fscq-impl,mit-pdos/fscq-impl,mit-pdos/fscq-impl,mit-pdos/fscq-impl