OctoPrint port and listening IP can now be configured
First-time and Octo-Config now use a shared library reducing duplicate
code
Reverted output files to default format
Updated TODO
GUI has been implemented using NoDM
Some files have been shifted to more appropriate stages
Updated the name in NOOBS (although whats the point?)
OctoPrint is now built and installed
Removed LightDM as its a buggy mess
The `(..)/raspberrypi-kernel/changelog.Debian.gz` file is not guaranteed
to be present in the built `ROOTFS_DIR`, for example when building very
minimal images without package documentation. In these cases, the `firmware`
variable will be left empty and the subsequent calls to `curl` will return
large 404 HTML content from GitHub.
Instead, simply check if the changelog file exists before using it.