systemctl: further refactoring (with credits to openfbtd [fleshless.org])
systemctl: implement most unit options
tmpfiles.d: add /run/systemd/manager/load entry
cgroup: indent
main: unused variables and missing header
man: systemctl: fix some mismatched tags
core: make manager_dump_* functions inherently write to files
core: remove dedicated list-jobs, replace with dump and cat manager-job-dump
job, unit: add delimiter during dumps for easy text processing
systemctl: implement list-jobs, list-dependencies, show, is-active and is-failed