Housekeeping

- Update README
- Run shellcheck on .sh files
- Add helper scripts
- Remove eirene vm variant
- Add post-install checklist

Signed-off-by: Nikolaos Karaolidis <nick@karaolidis.com>

hosts/common/system/configs/timezone/timezone.sh

@@ -1,7 +1,7 @@
 case "$2" in
   connectivity-change)
     if timezone=$(curl --fail https://ipapi.co/timezone); then
-      timedatectl set-timezone "$timezone"
+      timedatectl set-timezone "${timezone}"
     fi
     ;;
 esac