Update documentation of CSV header converter
git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@53628 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
Update documentation of CSV header converter
r45498, [GH-575]. [Fix GH-1215]
git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@53628 b2dd03c8-39d4-4d8f-98ff-823fe69b080e