Ability to delete originals after importing with "automatic organization"

Thanks, @Demosthenex and @whoopn, for cogitating on this some more, that was helpful!

So: I think having a new syncCopyHandler setting, with appropriate cautionary verbiage, should suffice here, that has 3 modes:

  1. retain: Retain duplicate files (this is the current behavior and will be the default)
  2. destroy: Immediately unlink all duplicate files during import
  3. mark-deletable: Mark duplicates as deletable in the database (which can then be unlinked via a nav menu “empty trash” dialog).

I’ll update the delete topic with why I’m hesitant to support “hidden files” or system trash.