prove reflexivity also for the quotient composition relation; reflp_preserve renamed to reflexivity_rule
#contributed components
contrib/cvc3-2.2
contrib/e-1.5
contrib/hol-light-bundle-0.5-126
contrib/kodkodi-1.2.16
contrib/spass-3.8ds
contrib/scala-2.9.2
contrib/vampire-1.0
contrib/yices-1.0.28
contrib/z3-3.2