DevStack likes to use LC_ALL=en_US.UTF-8 because it does some
post-processing of output that depends on stable sort-order. Pull in
the langpack package that provides this by default -- fedora-minimal
was doing this via yum-minimal so it makes sense to be equivalent.
Change-Id: I799bcfd73e1cb76ee1808b3441f40b0525e3c73d
Add dnf-plugins-core to the package-installs; this lets things like
"dnf copr" work automatically and is in-line with fedora-minimal base
packages. While we're here, clean up some unneeded packages, and
remove the pkg-map that isn't relevant for Fedora builds.
Change-Id: Iad5a4717bcb55928377cc159b3360b0a70c5c5ac