Log Message:
Update to 5.2.10.

Gutenprint 5.2.10 no longer supports Macintosh OS X 10.4 or earlier.

[See NEWS for the list of printers; ~1000 lines were omitted from this
commit message.]

  1) Added a unified CUPS backend to support selected dye sublimation
     printers.

  2) New printers supported in this release:

     [many]

  3) The following Canon printer models were not added, as they cannot
     currently be supported, even experimentally, owing to an as-yet
     unknown command format or other issues:

     [several]

  4) Corrected page dimensions for borderless printing with Canon
     inkjet printers.

  5) Added duplex support for the EPSON WorkForce 630, 635, and 645,
     and NX635

  6) Expanded printable area at the bottom of the page for the Epson
     Stylus Pro 3800 and 3880.

  7) Added IEEE1284 device IDs for the following printers.

     [many]

  8) Added Catalan, Turkish, and Vietnamese translations.