This moves libsystemd.so and libudev.so into systemd.lib, and gets rid
of libudev (which just contained a copy of libudev.so and the udev
headers). It thus reduces the closure size of all packages that
(indirectly) depend on libsystemd, of which there are quite a few (for
instance, PulseAudio and dbus). For example, it reduces the closure of
Blender from 430.8 to 400.8 MiB.
- systemd puts all into one output now (except for man),
because I wasn't able to fix all systemd/udev refernces
for NixOS to work well
- libudev is now by default *copied* into another path,
which is what most packages will use as build input :-)
- pkgs.udev = [ libudev.out libudev.dev ]; because there are too many
references that just put `udev` into build inputs (to rewrite them all),
also this made "${udev}/foo" fail at *evaluation* time
so it's easier to catch and change to something more specific
This seems to have been confusing people, using both xlibs and xorg, etc.
- Avoided renaming local (and different) xlibs binding in gcc*.
- Fixed cases where both xorg and xlibs were used.
Hopefully everything still works as before.
