[Pkg-emacsen-addons] Bug#906528: dh-elpa: support elpa version number of 0

[David Bremner]

Package: dh-elpa
Version: 1.13
Severity: normal

if the version number is 0, then the check around line 154 of dh_elpa
fails, because it checks for a falsy value.

-- System Information:
Debian Release: buster/sid
  APT prefers testing
  APT policy: (900, 'testing')
Architecture: amd64 (x86_64)

Kernel: Linux 4.17.0-1-amd64 (SMP w/8 CPU cores)
Locale: LANG=en_CA.UTF-8, LC_CTYPE=en_CA.UTF-8 (charmap=UTF-8), LANGUAGE=en_CA:en (charmap=UTF-8)
Shell: /bin/sh linked to /bin/dash
Init: systemd (via /run/systemd/system)
LSM: AppArmor: enabled

Versions of packages dh-elpa depends on:
ii  debhelper               11.3.5
ii  dh-make-perl            0.102
ii  emacs25                 1:25.2+1-7
ii  libarray-utils-perl     0.5-1
ii  libconfig-tiny-perl     2.23-1
ii  libdebian-source-perl   0.102
ii  libdpkg-perl            1.19.0.5
ii  libfile-find-rule-perl  0.34-1
ii  libtext-glob-perl       0.10-1
ii  perl                    5.26.2-7

dh-elpa recommends no packages.

dh-elpa suggests no packages.

-- no debconf information