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.
- preservefiles generally needs to have the target filesystems
mounted, so that it can preserve to them; but you can also
configure it such that there is no need for mounted filesystems
(e.g. in OEM setup).
- Add an example line in CMakeLists.txt to show how that would be done.
- more flexible way to keep (all kinds of) files from the host
system, into the target system.
- WIP: substitutions like in shellprocess (@@ROOT@@, @@HOME@@ probably)
- WIP: creating a JSON file from global settings
