Tweaks to resolve some regressions

In #214, updates that did not need an XML tree were separated from those that do.

Applying this to another reg brought some bugs. In some cases, we rely on order, and we assume the MOVE, etc. operations (XMLless) happen *before* edits. Instead of figuring out the delay, I've just re-ordered the execution.

Also, fixes an issue where an amendment to a different cfr part got associated with the following cfr part.