Finalise new R formula for R2MLwiN 

git-svn-id: svn://svn.r-forge.r-project.org/svnroot/r2mlwin@220 edb9625f-4e0d-4859-8d74-9fd3b1da38cb
relative changes since the new R formula introduced

git-svn-id: svn://svn.r-forge.r-project.org/svnroot/r2mlwin@221 edb9625f-4e0d-4859-8d74-9fd3b1da38cb