* enc/trans/utf_16_32.c: new file, currently implementing
UTF-16BE conversions only.
* test/ruby/test_transcode.rb: Added tests for UTF-16BE;
made check_both_ways() use force_encoding differently.
* transcode_data.h, transcode.c: Support for more conversion
functions.
git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@15142 b2dd03c8-39d4-4d8f-98ff-823fe69b080e