residuals.selection( , part = "outcome" ) now works for models with binary dependent outcome variables: argument "type" is used to determine the type of the residuals

git-svn-id: svn://svn.r-forge.r-project.org/svnroot/sampleselection@1556 d36ae590-6c38-44c5-9ba5-7217e93607d8
added further tests for residuals.selection()

git-svn-id: svn://svn.r-forge.r-project.org/svnroot/sampleselection@1557 d36ae590-6c38-44c5-9ba5-7217e93607d8