enable writing out iterations

Two-phase-Richards/multi-patch/layered_soil_with_inner_patch/TP-R-layered_soil_with_inner_patch-realistic.py

@@ -148,7 +148,7 @@ else:
     write_to_file = {
         'space_errornorms': True,
         'meshes_and_markers': True,
-        'L_iterations_per_timestep': False,
+        'L_iterations_per_timestep': True,
         'solutions': True,
         'absolute_differences': True,
         'condition_numbers': analyse_condition,