to a dual license with 2-clause BSDL.
[ruby-dev:42166] [ruby-core:31971]
[ruby-dev:39167] [ruby-core:25272]
* COPYING.ja: ditto.
* BSDL: added. this is from The FreeBSD License.
git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@29262 b2dd03c8-39d4-4d8f-98ff-823fe69b080e