deskutils/crengine-ng: Update to 0.9.13

Adds support for the WebP image format.

Reported by: Kostas Oikonomou <k.oikonomou@att.net> (mail)
Tested by: Kostas Oikonomou <k.oikonomou@att.net> (mail)
Approved by: arrowd (co-mentor)

(cherry picked from commit e9e6ed1f53f71d4f78d8ecf0081729d0339346bb)