some tests with constant feature


git-svn-id: svn://svn.r-forge.r-project.org/svnroot/easyabc@379 edb9625f-4e0d-4859-8d74-9fd3b1da38cb
1.3.1 changes


git-svn-id: svn://svn.r-forge.r-project.org/svnroot/easyabc@380 edb9625f-4e0d-4859-8d74-9fd3b1da38cb