added 'head nil' example git-svn-id: https://svn-agbkb.informatik.uni-bremen.de/Hets/trunk@3662 cec4b9c1-7d33-0410-9eda-942365e851bb
test function type extraction git-svn-id: https://svn-agbkb.informatik.uni-bremen.de/Hets/trunk@3661 cec4b9c1-7d33-0410-9eda-942365e851bb