use signal for default label creation

issue/signals.py

@@ -0,0 +1,13 @@
+from django.db.models.signals import post_save
+from django.dispatch import receiver
+
+from issue.models import Project, Label
+
+
+@receiver(post_save, sender=Project, dispatch_uid="Create default project labels.")
+def create_default_project_labels(sender, **kwargs):
+    if kwargs['created']:
+        project = kwargs['instance']
+        Label(project=project, name='bug', color='#FF0000').save()
+        Label(project=project, name='feature', color='#00A000').save()
+        Label(project=project, name='documentation', color='#1D3DBE').save()