fixed logic for deletion of voter

fabfile.py

@@ -36,6 +36,7 @@ def check_tag(tag, path):
 
     with cd(path):
         run('git pull origin master')
+        run('git fetch --tags')
         result = run('git tag')
         if tag not in result.split("\n"):
             abort("no remote tag %s" % tag)

helios/views.py

@@ -634,7 +634,8 @@ def voter_delete(request, election, voter_uuid):
   - election is not frozen or
   - election is open reg
   """
-  if not (election.frozen_at or election.openreg):
+  # if election is frozen and has closed registration
+  if election.frozen_at and (not election.openreg):
     raise PermissionDenied()
 
   if election.encrypted_tally: