* share/doc/developers_guide_ja.texi : Update versions of the current
  development environment.
* lib/adlint/cc1/parser.y : Revise the parser generation rule in order
  to accept extra semicolons in the global scope.
* features/code_check/E0018.feature : Ditto.
* etc/mesg.d/core/ja_JP/messages.yml : Ditto.
* etc/mesg.d/core/en_US/messages.yml : Ditto.
* share/doc/users_guide_ja.texi : Ditto.
* share/doc/users_guide_en.texi : Ditto.
Bump version for 3.2.6 GA release