Fix blacklist vpermit_required (#1452)

* - Adjusted blacklist argument default to False
- Tweaked description

* - Fix blacklist vpermit rejecting validators instead of non-validators

* - Blacklist vpermit return true without permit, return false with permit

* - Added text response to the return value for vpermit

bittensor/_blacklist/__init__.py

@@ -113,7 +113,10 @@ def blacklist(
             and is_registered
         ):
             uid = metagraph.hotkeys.index(src_hotkey)
-            return metagraph.neurons[uid].validator_permit
+            # Return False (pass) if there is a permit, and True (fail) if there isn't.
+            if metagraph.neurons[uid].validator_permit:
+                return False, "has vpermit"
+            return True, "no vpermit"
 
         # All checks passed.
         return False, "passed blacklist"