1 - delete mobile-action-modeswitch
2 (moved to usb_modeswitch)
4 - /run/udev/control socket
5 (add ConditionVirtualization=!pidns)
7 - kill rules_generator:
8 - no longer rename netifs in kernel namespace
9 - drop persistent optical names
10 - do not create rules on-the-fly, require explicit configuration
11 for netifs and optical drives
12 - properly document what system management needs to put
17 - remove deprecated trigger --type=failed logic
19 - remove deprecated BUS=, SYSFS{}=, ID= keys