Updated information in SHOW AUTHORS and SHOW CONTRIBUTORS
SHOW AUTHORS and SHOW CONTRIBUTORS are not depricated anymore.

CMakeLists.txt:
  Install TODO and CREDITS files
CREDITS:
  Information about the MariaDB foundation
README:
  Updated to include the MariaDB foundation
mysql-test/r/contributors.result:
  Updated contributors
mysql-test/r/show_check.result:
  SHOW AUTHORS and SHOW CONTRIBUTORS are not depricated anymore.
scripts/make_binary_distribution.sh:
  Added TODO and CREDITS
sql/authors.h:
  Updated list of active authors
sql/contributors.h:
  Updated list of active contributors and members of the MariaDB foundation
sql/sql_show.cc:
  Extend comment lengths
sql/sql_yacc.yy:
  SHOW AUTHORS and SHOW CONTRIBUTORS are not depricated anymore