store style/scale as attributes in rootogram objects so that they can
be reused in c() and + methods



git-svn-id: svn://svn.r-forge.r-project.org/svnroot/countreg@86 edb9625f-4e0d-4859-8d74-9fd3b1da38cb
minor cosmetic changes

git-svn-id: svn://svn.r-forge.r-project.org/svnroot/countreg@87 edb9625f-4e0d-4859-8d74-9fd3b1da38cb
new version

git-svn-id: svn://svn.r-forge.r-project.org/svnroot/countreg@88 edb9625f-4e0d-4859-8d74-9fd3b1da38cb