The build system can now find and integrate my very own psurface

library.  psurface handles parametrized triangulated surface in 3d.
In particular it can be used to have 3d UGGrids with parametrized
boundaries.

[[Imported from SVN: r266]]

configure.ac

@@ -67,7 +67,10 @@ echo
 DUNE_PATH_ALBERTA
 # UG-check
 DUNE_PATH_UG
+# Check for the AmiraMesh library
 DUNE_PATH_AMIRAMESH
+# Check for the psurface library
+DUNE_PATH_PSURFACE
 # Yaspgrid-check
 DUNE_MPI