Rename test for multiple similar matches

A rename test that illustrates a source matching multiple targets.
Update rename src map for any split src

When using a rename source that is actually a to-be-split record,
we have to update the best-fit mapping data in both the case where
the target is also a split record and the case where the target
is a simple added record.  Before this commit, we were only doing
the update when the target was itself a split record (and even in
that case, the test was slightly wrong).
Rename test for rename from rewrite

A rename test that illustrates a rename from a rewrite.
Restore commented out tests

This restores the commented out tests (even though they're slow)
and fixes some trailing whitespace.