for some of these files this is needed to make to keep it compiling
after the next patch because the new ErrorMacros.hpp file will no
longer implicitly includes <iostream>. for the remaining files it is
just good style.
While at it, the includes for most of these files have been ordered in
order of decreasing abstraction level.
The attic are the place where files which we don't use right now, but
which we acknowledge some amount of valuable time has been spent on and
which may be usable some day in the future, so we don't have the
conscience to right out delete them.
These files are not expected to compile, and certainly not to run and
produce sensible results, anymore. However, with some work they can
possibly be converted into proper unit tests or examples.
Andreas Lauser
Roland Kaufmann