- point to main Calamares site in the 'part of' headers instead
of to github (this is the "this file is part of Calamares"
opening line for most files).
- remove boilerplate from all source files, CMake modules and completions,
this is the 3-paragraph summary of the GPL-3.0-or-later, which has
a meaning entirely covered by the SPDX tag.
The intended license for the CMake modules is BSD-2-Clause;
there's no desire to restrict what can be done with these,
and CMake modules are generally 2-clause licensed.
- This makes linking easier,
- Adds the right includes (needed on FreeBSD),
- Lets us drop silly GUI setting for non-GUI tests (I think this was
a side-effect of compiling on FreeBSD, where UI would pull in
/usr/local/include).
