Make systemctl is-enabled work for templated units

Hello guys,

in this mail, you will find a patch which resolves the problem, that 'systemctl is-enabled' does not work for templated units.

See also https://bugs.freedesktop.org/show_bug.cgi?id=55318 for reference.

Without this patch, systemctl is-enabled something@abc.service returned "No such file or directory", because it was checked if /usr/lib/systemd/system/something@abc.service, etc. existed, which is obviously not the case.

If systemctl is-enabled is called for templated units, this check should be omitted and it should be searched for symlinks in the /etc paths right away.

I would like to request that this is merged to the systemd git tree.

Best, -Michael