Revert logic that assumes all themes use buefy

that just isn't a safe assumption yet..alas

tailbone/util.py

@@ -209,8 +209,13 @@ def should_use_buefy(request):
     if buefy is not None:
         return buefy
 
-    # otherwise assume buefy is in effect
-    return True
+    # TODO: should not hard-code this surely, but works for now...
+    if theme == 'falafel':
+        return True
+
+    # TODO: probably should not use this fallback? it was the first setting
+    # i tested with, but is poorly named to say the least
+    return request.rattail_config.getbool('tailbone', 'grids.use_buefy', default=False)
 
 
 def pretty_datetime(config, value):