* Support suites other than Stretch
* Insert suite into image filename
* Fix installing Firefox on Sid
* Fix downloading Chromium on Sid
* Don't use sid-updates or security sid/updates
Fixed:
filesystems were created with journaling disabled, now journaling is enabled
filesystem was mounted rw on boot, which prevented fsck from running
- changed to ro, which then gets mounted as rw by systemd using the fstab file
- added a fstab for the external boot devices that tries both usb and sd card
