initial voidlinux changes

[anuejn]

known issues / todos:

• the control daemon does not compile because it still depends on systemd
• the global bashrc is not sourced, it needs to go to /etc/bashrc.d/ or something like that
• lighttpd is not autostarted, ln -sf /etc/sv/lighttpd /etc/runit/runsvdir/default/
• runit does its dependency management the other way around as systemd which means to generate the /etc/issue file intime we need to patch the agetty-console target / copy and modify it (we don't want to patch it, because it will probably get replaced by system updates)
• some unnecessary packages are still installed, decide what packages we need and what we can remove (do we need things like xfsprogs?)
• the axiom-start service needs to be ported to runit
• which python version do we want / need for the python scripts? (currently their dependencies are installen for python2.7, any reason not to use python3.7 / python3.8 ?