MR comments

- NO_ACCESS_ROLE_ID constant moved to models.py
- added docstring for batch create request body

areas/roles/models.py

@@ -3,6 +3,8 @@ from database import db
 
 
 class Role(db.Model):
+    NO_ACCESS_ROLE_ID = 3
+
     id = db.Column(Integer, primary_key=True)
     name = db.Column(String(length=64))