wrong sort order in cbz files

[Moses Moore]

Seen:
 - pages in a .cbz archive are displayed out-of-order

Steps to reproduce:
 - TMP=$(mktemp -d)
 - cd $TMP
 - for n in 01 02 03 04 05 06 07 08 09 0a 0b 0c 0d 0e 0f 0A 0B 0C 0D 0E 0F; do convert -background lightblue -fill blue -pointsize 72 label:"$n" $n.png ; done
 - zip $TMP.cbz *.png
 - qcomicbook $TMP.cbz

Expected:
 - pages displayed will be in alphabetical order, same order as `ls $TMP |sort` : 01, 02, ... 09, 0A, 0a, 0B, 0b, ...
 - or pages displayed will be in byte order, same order as `ls $TMP |LC_ALL=C sort` : 01, 02, ... 09, 0A, 0B, ... 0F, 0a, 0b, ...

Seen:
 - pages are displayed in a strange order: 0A, 0B, 0C, 0D, 0E, 0F, 0a, 0b, 0c, 0d, 0e, 0f, 01, 02, 03, ...

ProblemType: Bug
DistroRelease: Ubuntu 18.04
Package: qcomicbook 0.9.1-2
ProcVersionSignature: Ubuntu 4.15.0-30.32-generic 4.15.18
Uname: Linux 4.15.0-30-generic x86_64
NonfreeKernelModules: nvidia_modeset nvidia
ApportVersion: 2.20.9-0ubuntu7.2
Architecture: amd64
CurrentDesktop: XFCE
Date: Tue Aug 28 00:23:04 2018
InstallationDate: Installed on 2016-06-05 (813 days ago)
InstallationMedia: Xubuntu 16.04 LTS "Xenial Xerus" - Release amd64 (20160420.1)
SourcePackage: qcomicbook
UpgradeStatus: Upgraded to bionic on 2018-04-27 (123 days ago)