test/MpNc: add grid files

git-svn-id: svn://svn.iws.uni-stuttgart.de/DUMUX/dumux/trunk@6666 2fb0f335-1f38-0410-981e-8018bf24f1b0

test/boxmodels/MpNc/grids/2pNc_obstacle.dgf

+DGF
+Interval
+0 0   % first corner 
+60 40   % second corner
+24 16   % 24 cells in x and 16 in y direction
+#
+GridParameter
+overlap 0 
+periodic 
+closure green
+#GridParameter 
+BOUNDARYDOMAIN
+default 1    % all boundaries have id 1
+#BOUNDARYDOMAIN
+# unitcube.dgf 

test/boxmodels/MpNc/grids/2pNc_obstacle_48x32.dgf

+DGF
+Interval
+0 0   % first corner 
+60 40   % second corner
+48 32   % 24 cells in x and 16 in y direction
+#
+GridParameter
+overlap 0 
+periodic 
+closure green
+#GridParameter 
+BOUNDARYDOMAIN
+default 1    % all boundaries have id 1
+#BOUNDARYDOMAIN
+# unitcube.dgf