Don't want to disable indexing, just stop re-indexing

[dnanian]

I brought this particular issue up numerous times in various sessions throughout WWDC, in the context of backing things up AND copying. Because, the fact is, these non-importer related metadata items are not backed up, and don't follow the file when copied.

So, it's hardly just reindexing. It's pretty much everything. Including backing up.

Spotlight has a lot of good things in it, but it doesn't have a lot of good data management issues for cases like this. (Fortunately, virtually everything in the database comes in through the importer -- everything but kMDItemWhereFrom -- and that is duplicated in the Spotlight comment, which *is* backed up.)