* machined, localed: when we try to kill an empty cgroup, generate an ESRCH error over the bus
* libsystemd-journal, libsystemd-login, libudev: add calls to easily attach these objects to sd-event event loops
* machined, localed: when we try to kill an empty cgroup, generate an ESRCH error over the bus
* libsystemd-journal, libsystemd-login, libudev: add calls to easily attach these objects to sd-event event loops