The build instructions are not that interesting, it's a toss-up
between CC0 and BSD-2, but because other CMake bits are BSD-2-Clause,
apply that to more CMakeLists. The copyright date isn't all that
accurate, but these are just inconsequential files.
While here, tidy up and get rid of some useless intermediates.
- Although it's not necessarily accurate for an extensively-modified
Plasma configuration, we can read the Look-and-Feel from the
configuration files. Allows auto-detection.
