Fix: Install lftools before other packages

lftools has an incompatibility with python-docker >4.2, and this
requirement seems to be causing a conflict with other packages that
python-tools-install is installing. This causes an older version of
lftools to be installed (0.31.1, the last version when docker was not
pinned).

By installing lftools first, its requirements will take
precedence over other packages.

Issue: RELENG-3792
Change-Id: I0d3ca88dbe51c97ce495f6db0eb66829a61ad3bc
Signed-off-by: Eric Ball <eball@linuxfoundation.org>