(HTCONDOR-362) Do not attempt to start minicondor if no systemd.
(HTCONDOR-362) Do not attempt to start minicondor if no systemd.

The minicondor (minihtcondor) DEB package attempts to launch the
htcondor service via systemctl commands at the end of the install.  This
always fails on stock Debian and Ubuntu containers because these
containers do not have systemd, and thus do not even have systemctl
commands installed. This commit will first check for the systemctl
commands before trying (and failing) to use them.

htcondor/htcondor,htcondor/htcondor,htcondor/htcondor,htcondor/htcondor,htcondor/htcondor,htcondor/htcondor,htcondor/htcondor,htcondor/htcondor