The multi-argument CompressFiles(...) method has been replace by the
no-argument PackageFiles() method and 3 more member variables. This
will enable implemention of multi-package generators. Now each specific
generator (which overloads PackageFiles()) may decide to change the name
and/or the number of generated package files.
This converts the CMake license to a pure 3-clause OSI-approved BSD
License. We drop the previous license clause requiring modified
versions to be plainly marked. We also update the CMake copyright to
cover the full development time range.
