Features:
+* open up creds for uses in generators, and document clearly that encrypted
+ creds are only supported if strictly tpm bound, but not when using the host
+ secret (as that is only avilable if /var/ is around.
+
+* logind: when logging in, always take an fd to the home dir, to keep the dir
+ busy, so that autofs release can never happen. (this is generally a good
+ idea, and specifically works around the fact the autofs ignores busy by mount
+ namespaces)
+
* mount most file systems with a restrictive uidmap. e.g. mount /usr/ with a
uidmap that blocks out anything outside 0…1000 (i.e. system users) and similar.