Log Message:
Update to 0.6.13.

New in 0.6.13:

  * Bug fixes: #803191, #1051994, #1054321, #1054323, #1196787

  * For pkg-config users, force usage of #include <libexif/exif-*.h>
    (disable #include <exif-.h>)

  * Updated German translation

  * Build system tuning

  * Misc changes:
    Fix COPYRIGHT tag, fix memory corruption, use qsort.