Features:
+* use sd-event ratelimit feature optionally for .socket units to "pause" overly
+ busy sockets temporarily. (as a less drastic version of the trigger
+ ratelimit)
+
+* similar, add the same for journal stream clients that log too much
+
+* systemd-mount sould only consider modern file systems when mounting, similar
+ to systemd-dissect
+
* new "systemd-pcrlock" component for dealing with PCR4. Design idea:
1. define /{etc,usr,var/lib}/pcrlock.d/<component>/<version>.pcrlock
2. these files contain list of hashes that will be measured when component is