gpg: Change armor Version header to emit only the major version.
* g10/options.h (opt): Rename field no_version to emit_version. * g10/gpg.c (main): Init opt.emit_vesion to 1. Change --emit-version to bump up opt.emit_version. * g10/armor.c (armor_filter): Implement different --emit-version values.
- GnuPG-bug-id: T1572
- Signed-off-by: Werner Koch <wk@gnupg.org>