merge trunk up to 1371 into centaur

git-svn-id: http://acl2-devel.googlecode.com/svn/branches/centaur@1386 5d84a466-a78b-0930-a311-59b22171a541
merge up to r1385

git-svn-id: http://acl2-devel.googlecode.com/svn/branches/centaur@1387 5d84a466-a78b-0930-a311-59b22171a541