[cleanup][tests] Use new standard grid creator for zeroeq

* Use input file for structured grids instead of dgf files for
  zeroeq tests

test/freeflow/zeroeq/grids/channel.dgf

-DGF
-Interval
-0 0   % first corner
-5.0 1.5  % second corner
-25 15 % cells in x and y direction
-#
-
-Cube
-0 1 2 3
-#
-
-BOUNDARYDOMAIN
-default 1 % all boundaries have id 1
-#BOUNDARYDOMAIN
-# unitcube.dgf

test/freeflow/zeroeq/grids/pipe.dgf

-DGF
-Interval
-0 0   % first corner
-10 0.2469  % second corner
-20 40 % cells in x and y direction
-#
-
-Cube
-0 1 2 3
-#
-
-BOUNDARYDOMAIN
-default 1 % all boundaries have id 1
-#BOUNDARYDOMAIN
-# unitcube.dgf

test/freeflow/zeroeq/test_zeroeq.input

@@ -3,7 +3,9 @@ DtInitial = 5 # [s]
 TEnd = 50 # [s]
 
 [Grid]
-File = grids/pipe.dgf
+LowerLeft = 0 0
+UpperRight = 10 0.2469
+Cells = 20 40
 
 [Problem]
 OutputName = "zeroeq"

test/freeflow/zeroeq/test_zeroeq_channel.input

@@ -3,7 +3,9 @@ DtInitial = 0.001 # [s]
 TEnd = 10 # [s]
 
 [Grid]
-File = grids/channel.dgf
+LowerLeft = 0 0
+UpperRight = 5.0 1.5
+Cells = 25 15
 
 [Problem]
 OutputName = "zeroeqchannel"

test/freeflow/zeroeq/zeroeqchanneltestproblem.hh

@@ -23,12 +23,6 @@
 #ifndef DUMUX_ZEROEQCHANNELTESTPROBLEM_HH
 #define DUMUX_ZEROEQCHANNELTESTPROBLEM_HH
 
-#if HAVE_UG
-#include <dune/grid/io/file/dgfparser/dgfug.hh>
-#else
-#include <dune/grid/io/file/dgfparser/dgfyasp.hh>
-#endif
-
 #include <dumux/material/fluidsystems/h2oair.hh>
 #include <dumux/material/fluidsystems/gasphase.hh>
 

test/freeflow/zeroeq/zeroeqtestproblem.hh

@@ -26,12 +26,6 @@
 #ifndef DUMUX_ZEROEQTESTPROBLEM_HH
 #define DUMUX_ZEROEQTESTPROBLEM_HH
 
-#if HAVE_UG
-#include <dune/grid/io/file/dgfparser/dgfug.hh>
-#else
-#include <dune/grid/io/file/dgfparser/dgfyasp.hh>
-#endif
-
 #include <dumux/material/fluidsystems/h2oair.hh>
 #include <dumux/material/fluidsystems/gasphase.hh>