1 - validate the two hex chars in replace_chars \x
3 - test (now fixed) /dev/tape/ links
5 - /run/udev/control socket
6 (add ConditionVirtualization=!pidns)
8 - move udevd -> --libexecdir
12 - kill rules_generator
14 - move udevadm -> --bindir
18 - warn about RUN+="socket:"
20 - libudev.so.1 with symbol versioning:
21 - return object with *_unref()
22 - udev_monitor_from_socket()