Add command to remove rank from skill

ultron/objective/management/commands/remove_rank_from_skill.py

@@ -0,0 +1,13 @@
+""" supprime le rank des skill
+"""
+
+from django.core.management.base import BaseCommand
+from ultron.objective.models import Skill
+
+
+class Command(BaseCommand):
+    def handle(self, *args, **options):
+        skill_list = Skill.objects.all()
+        for skill in skill_list:
+            skill.rank = 0
+            skill.save()