test-revert: add case where wc content is different from "base" and "parent"
This test highlights a case where backups are not created and the user may
lose data.
FROM fedora
RUN yum install -y gcc
RUN yum install -y python-devel python-docutils
RUN yum install -y make
RUN yum install -y rpm-build
RUN yum install -y gettext