Log Message:
Update to 1.0.13. From the changelog:

* omindex:
  + If the filter program needed for a file format isn't installed, report this
    explicitly when skipping subsequent files with the extension instead of
    misleadingly reporting "Unknown extension".
  + Make -s actually work as a short-form for --stemmer (as documented by
    "omindex --help" and "man omindex").
  + Drop the copyright info from the output of --version as it's perennially
    out of date and we don't report it for any other Xapian programs.
* scriptindex:
  + Add new "valuenumeric" action to add a document value using
    Xapian::sortable_serialise() to allow numeric sorting (ticket#260).