switched both vignettes to \documentclass[nojss]{jss} properly and then
removed old Z.cls

updated a few references, and added e-mail addresses in affiliation section



git-svn-id: svn://svn.r-forge.r-project.org/svnroot/vcd@750 edb9625f-4e0d-4859-8d74-9fd3b1da38cb