Update d/copyright

Copyright: 2019 Christopher Chang

License: LGPL-3+

Files: SFMT.*

Files: include/SFMT.*

Copyright: 2006-2012 Mutsuo Saito, Makoto Matsumoto, Hiroshima University and The University of Tokyo

License: BSD-3-clause

Files: pgenlib_ffi_support.*

       pgenlib_misc.*

       pgenlib_read.*

       pgenlib_write.*

       plink2_base.*

       plink2_bgzf.*

       include/pgenlib_misc.*

       include/pgenlib_read.*

       include/pgenlib_write.*

       include/plink2_base.*

       include/plink2_bgzf.*

       plink2_cmdline.*

       plink2_common.*

       plink2_compress_stream.*

       plink2_decompress.*

       plink2_psam.h

       plink2_random.*

       plink2_stats.h

       plink2_string.*

       plink2_text.*

       plink2_thread.*

       plink2_zstfile.*

       include/plink2_stats.h

       include/plink2_string.*

       include/plink2_text.*

       include/plink2_thread.*

       include/plink2_zstfile.*

       pvar_ffi_support.*

Copyright: 2005-2019 Shaun Purcell, Christopher Chang

License: LGPL-3+