Suggested Update to PhotoTaggingGramplet to Support XMP Face Regions

Development
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An invalid Rectangle breaks Import and Export. This failure cripples restoring a backup .gpkg file. It creates unusable backups without any alerts.

See

The failure was traced back to a corrupted handle for a objref the <people></people> XML chunk. The block was for a tagging rectangle in an image Media object. That was from the Photo Tagging gramplet.
Oddly, there were TWO separate objref tags (covering different region coordinates) for the Person object. The first had a valid handle, the 2nd had a NULL handle with ONLY an underscore.

      <objref hlink="_">
       <region corner1_x="87" corner1_y="66" corner2_x="99" corner2_y="75"/>
      </objref>