Fortran error tests

Fortran error tests should be added, as suggested in #13 (closed).

For this some things have to be reworked, additional error checking enabled (such as correct permissions for already existing VTK output directories), that we can use to test against.

example/ALL_Staggered_f.F90

@@ -139,7 +139,7 @@ contains
         integer :: my_rank, maximum_rank
         integer :: i,j
         type(ALL_t) :: jall
-#ifdef ALL_VTK_OUTPUT
+#ifdef ALL_VTK_OUTPUT_EXAMPLE
         character (len=ALL_ERROR_LENGTH) :: error_msg
 #endif
 
@@ -209,7 +209,7 @@ contains
                 write(stdout,'(a,i0,"/",i0)') "Starting step: ", current_step, number_of_steps
                 flush(stdout)
             endif
-#ifdef ALL_VTK_OUTPUT
+#ifdef ALL_VTK_OUTPUT_EXAMPLE
             call ALL_reset_error()
             call jall%print_vtk_outlines(current_step)
             if(ALL_error() /= 0) then
@@ -227,7 +227,7 @@ contains
 
             call MPI_Barrier(MPI_COMM_WORLD, error)
         enddo
-#ifdef ALL_VTK_OUTPUT
+#ifdef ALL_VTK_OUTPUT_EXAMPLE
         call ALL_reset_error()
         call jall%print_vtk_outlines(current_step)
         if(ALL_error() /= 0) then