- The sources were in src/calamares but processed and generated
in libcalamares, which is weird at best.
- Generate an "extended" version header.
- Use the extended version in the logger and nowhere else.
- While here, minor coding style cleanups
The overall change here means that after running CMake, only
Logger.cpp needs to be rebuilt (if the extended version has
changed) and not a handful of other files that don't need the
full version number, but do happen to include CalamaresVersion.h
