unify the grids for the tests, all use unitcube.

dune/fem-dg/examples/grids/unitcube3.dgf

@@ -3,7 +3,7 @@ DGF
 Interval
 0 0 0  % first corner
 1 1 1  % second corner
-1 1 1  % 1 cell in each direction (x, y, z)
+4 4 4  % 1 cell in each direction (x, y, z)
 # 
 
 BoundaryDomain

dune/fem-dg/examples/navierstokes/test/parameter_cmake

@@ -45,9 +45,9 @@ kGNS: 3.1415926535897932385
 
 # DOMAIN CONFIGURATION
 #---------------------
-fem.io.macroGridFile_1d:  ../../grids/nswaves_1d.dgf
-fem.io.macroGridFile_2d:  ../../grids/nswaves_2d.dgf
-fem.io.macroGridFile_3d:  ../../grids/nswaves_3d.dgf
+fem.io.macroGridFile_1d:  ../../grids/unitcube1.dgf
+fem.io.macroGridFile_2d:  ../../grids/unitcube2.dgf
+fem.io.macroGridFile_3d:  ../../grids/unitcube3.dgf
 
 
 # SOLVER CONFIGURATION