make excepton logger resistant against __repr__ exceptions

git-svn-id: https://ekptrac.physik.uni-karlsruhe.de/svn/grid-control/trunk/grid-control@1194 29098800-e21f-4f28-a8ff-84ee76f0ac90
New config API

git-svn-id: https://ekptrac.physik.uni-karlsruhe.de/svn/grid-control/trunk/grid-control@1195 29098800-e21f-4f28-a8ff-84ee76f0ac90