fix cutData - remove any existing date-based types e.g. month, use date instead

git-svn-id: svn://svn.r-forge.r-project.org/svnroot/openair@826 edb9625f-4e0d-4859-8d74-9fd3b1da38cb
help file edit

git-svn-id: svn://svn.r-forge.r-project.org/svnroot/openair@827 edb9625f-4e0d-4859-8d74-9fd3b1da38cb