1 - support kernel-supplied DEVMODE=
3 - /run/udev/control socket
5 - read settle_timout from udev.conf
7 - db_persist -> lvm.git?
10 - no longer rename netif in kernel namespace
11 - do not create rules on-the-fly, require explicit
13 - drop persistent optical names
17 - remove deprecated trigger --type=failed logic
19 - remove deprecated BUS=, SYSFS{}=, ID= keys