MX-1270, fix rollback in the case where we encounter a bad fileop (like rename)
after we have passed lastGTID but before lastGTIDAfterSnapshot.
Also fix some test failures
MX-1273, use flags to forget about unique checks and locktree when calling updateOneObjectWithMods from secondaries
MX-1270, fix updates during that second phase
also add a little more test coverage to rollback in general
MX-1271 Rename fastupdate to fastUpdate
MX-1272, verify update flags before applying them