minimal bionic contains packages that are unnecessary

[Robert C Jennings]

There are packages in the minimal image that report being unneeded as soon as the user looks to install their first package.

Tested with daily bionic minimal LXD images (serial 20180328.1) from https://cloud-images.ubuntu.com/minimal/daily/bionic/

$ lxc remote add minimal-ubuntu-daily https://cloud-images.ubuntu.com/minimal/daily --protocol simplestreams
$ lxc launch minimal-ubuntu-daily:bionic b
$ lxc exec b -- apt autoremove --purge -y
Reading package lists... Done
Building dependency tree
Reading state information... Done
The following packages will be REMOVED:
  gettext-base* libfreetype6* libpng16-16*
0 upgraded, 0 newly installed, 3 to remove and 0 not upgraded.
After this operation, 1610 kB disk space will be freed.
(Reading database ... 14873 files and directories currently installed.)
Removing gettext-base (0.19.8.1-6) ...
Removing libfreetype6:amd64 (2.8.1-2ubuntu1) ...
Removing libpng16-16:amd64 (1.6.34-1) ...
Processing triggers for libc-bin (2.27-0ubuntu2) ...

[Scott Moser (smoser)]

possibly a dupe of bug 1721035.