test-strv: add test which shows access to random memory
Reject invalid quoted strings

String which ended in an unfinished quote were accepted, potentially
with bad memory accesses.

Reject anything which ends in a unfished quote, or contains
non-whitespace characters right after the closing quote.

_FOREACH_WORD now returns the invalid character in *state. But this return
value is not checked anywhere yet.

Also, make 'word' and 'state' variables const pointers, and rename 'w'
to 'word' in various places. Things are easier to read if the same name
is used consistently.

mbiebl_> am I correct that something like this doesn't work
mbiebl_> ExecStart=/usr/bin/encfs --extpass='/bin/systemd-ask-passwd "Unlock EncFS"'
mbiebl_> systemd seems to strip of the quotes
mbiebl_> systemctl status shows
mbiebl_> ExecStart=/usr/bin/encfs --extpass='/bin/systemd-ask-password Unlock EncFS  $RootDir $MountPoint
mbiebl_> which is pretty weird
Properly report invalid quoted strings

$ systemd-analyze verify trailing-g.service
[./trailing-g.service:2] Trailing garbage, ignoring.
trailing-g.service lacks ExecStart setting. Refusing.
Error: org.freedesktop.systemd1.LoadFailed: Unit trailing-g.service failed to load: Invalid argument.
Failed to create trailing-g.service/start: Invalid argument
core/load-fragment.c: correct argument sign and split up long lines

With everything on one line they are just harder to read.
systemd-analyze verify: improve error message

There's little sense in telling the user to look at the logs...
sysusers: split users for remote into separate file

This mirrors the setup for tmpfiles.d done in ad95fd1d2b9.
man: add missing comma
man: add udev.conf(5)

We generally have separate man pages for all configuration files.
In this case udev.conf was already described in systemd-udevd.service(8),
but it was hard to find. Docbook makes it hard to add a .so link from
a different section, so describe udev.conf in its own page.
Constify option table and add missing option
Always prefer our headers to system headers

In practice this shouldn't make much difference, but
sometimes our headers might be newer, and we want to
test them.
resolve-host: list types and classes

Also update systemctl to similar style.
resolved: MX records
resolved: TXT records
resolved: SPF records
resolved: LOC records

LOC records have a version field. So far only version 0 has been
published, but if a record with a different version was encountered,
our only recourse is to treat it as an unknown type. This is
implemented with the 'unparseable' flag, which causes the
serialization/deserialization and printing function to cause the
record as a blob. The flag can be used if other packet types cannot be
parsed for whatever reason.