Fix userland-software unit base part for Debian
Summary:
Currently, the userland-software unit base part doesn't work on Eglide.
The two main issues solved are:
- PHP 7.1 extensions packages on Debian haven't been check (fixes T1339).
- exiftool missing from the package map for Debian (fixes T1340)
Test Plan: salt eglide state.apply roles/shellserver/userland-software/base
Reviewers: dereckson
Reviewed By: dereckson
Differential Revision: https://devcentral.nasqueron.org/D1320