delete unwanted

git-svn-id: https://svn.code.sf.net/p/rubycocoa/svn/trunk/src@2549 f4f36d40-9719-0410-9868-dde021a23eda
Use $KCODE only for ruby-1.8

git-svn-id: https://svn.code.sf.net/p/rubycocoa/svn/trunk/src@2550 f4f36d40-9719-0410-9868-dde021a23eda