patches 6841 & 6842 (look for ug headers in include/ and include/ug/, to...

patches 6841 & 6842 (look for ug headers in include/ and include/ug/, to support new versions of ug) merged from the trunk

[[Imported from SVN: r6845]]

m4/ug.m4

@@ -70,7 +70,11 @@ AC_DEFUN([DUNE_PATH_UG],[
       
       # intermediate variables
       UG_LIB_PATH="$UGROOT/lib"
-      UG_INCLUDE_PATH="$UGROOT/include"
+	  if test -d "$UGROOT/include/ug/"; then
+        UG_INCLUDE_PATH="$UGROOT/include/ug/"
+	  else
+        UG_INCLUDE_PATH="$UGROOT/include/"
+	  fi
       
       UG_LDFLAGS=""