writable-paths: add additional paths for Systemd, fix disabling timesyncd
- /var/lib/private/systemd is used for state or runtime directories which (if I understand correctly) use DynamicUser=yes
- /etc/systemd/system is used for remembering enabled/disabled unit
- Removed: /etc/network/if-up.d
- Disable systemd-timesyncd.service on install, but enable it on first boot.
Requires https://github.com/Halium/initramfs-tools-halium/pull/38 to be fully functional as intended.
Fixes: #32 (closed)