add require/exclude test

Author: robertjwilson

data/chl/simulation/chl_bad_model.nc

@@ -43,7 +43,9 @@ def test_gridded(self):
             n_dirs_down = 0,
             ask = False,
             cache = True,
-            cores = 1
+            cores = 1,
+            require = "model", 
+            exclude = "bad"
         )
 
         ff = "oceanval_matchups/gridded/chlorophyll/foo_chlorophyll_surface.nc"