spelling errors --- didn't bother to upder DESCRIPTION or NEWS

git-svn-id: svn://svn.r-forge.r-project.org/svnroot/car@399 edb9625f-4e0d-4859-8d74-9fd3b1da38cb
More spelling error corrections.

git-svn-id: svn://svn.r-forge.r-project.org/svnroot/car@400 edb9625f-4e0d-4859-8d74-9fd3b1da38cb