"shared/nm-utils" contains general purpose utility functions that only
depend on glib (and extend glib with some helper functions).
We will also add code that does not use glib, hence it would be good
if the part of "shared/nm-utils" that does not depend on glib, could be
used by these future projects.
Also, we use the term "utils" everywhere. While that covers the purpose
and content well, having everything called "nm-something-utils" is not
great. Instead, call this "nm-std-aux", inspired by "c-util/c-stdaux".
(cherry picked from commit b434b9ec07)
For better or worse, we already pull in large parts of systemd sources.
I need a base64 decode implementation (because glib's g_base64_decode()
cannot reject invalid encodings). Instead of coming up with my own or
copy-paste if from somewhere, reuse systemd's unbase64mem().
But for that, make systemd's basic bits an independent static library
first because I will need it in libnm-core.
This doesn't really change anything except making "libnm-systemd-core.la"
an indpendent static library that could be used from "libnm-core". We
shall still be mindful about which internal code of systemd we use, and only
access functionality that is exposed via "systemd/nm-sd-utils-shared.h".
