initial version

git-svn-id: svn://svn.r-forge.r-project.org/svnroot/caret@844 edb9625f-4e0d-4859-8d74-9fd3b1da38cb
updated with new custom model and varImp link fix

git-svn-id: svn://svn.r-forge.r-project.org/svnroot/caret@845 edb9625f-4e0d-4859-8d74-9fd3b1da38cb