More improvements to mergeRules.
More improvements to mergeRules.

Using a defined beta-reduction op rather than simplifyOne, which is too
aggressive with simplifications like inlining.

git-svn-id: 9ecf60ce9baff443e30a0472d3fd222fcb8117cf@8258 7b97033b-253e-4a5c-9b07-e25f9089a9fd

KestrelInstitute/Specware,KestrelInstitute/Specware,KestrelInstitute/Specware,KestrelInstitute/Specware,KestrelInstitute/Specware