japanese/skkinput3: Remove invalid option

Remove RSKKSERV option (Depends on japanese/rskkserv expired in 2014-09)
Add LICENSE
Add japanese/skkserv option
If not selected in the options, do not install dictionary server
Switch post-install to post-install-DOCS-on
Sort options (pet portclippy)
Regenerate patches (pet portlint)
Add OPTIONS_SUB=yes and remove SKK10=*

PR: 279386
Approved by: koma2@lovepeers.org (maintainer, timeout > 1 month)