Merge branch 'change-playbook-repo' into 'master'

Add migration for playbook url

See merge request !68

tower/migrations/038_change_playbook_repo_to_noc.py

+
+# Third-party modules
+from peewee import CharField, Model
+
+
+def migrate(migrator):
+    class Environment(Model):
+        class Meta(object):
+            database = migrator.db
+            db_table = "environment"
+
+        name = CharField(unique=True)
+        playbook_link = CharField()
+
+    if len(Environment.select()) != 0:
+        for env in Environment.select():
+            if env.playbook_link == 'git+https://github.com/nocproject/ansible_deploy@microservices':
+                env.playbook_link = "git+https://github.com/nocproject/noc@stable"
+                env.save()