Added check for list title when creating a new list

REST-Tests/lists.http

@@ -0,0 +1,27 @@
+# Get all lists
+GET http://localhost:8080/api/v1/lists
+Authorization: Bearer {{auth_token}}
+
+###
+
+# Get one list
+GET http://localhost:8080/api/v1/lists/28
+Authorization: Bearer {{auth_token}}
+
+###
+
+# Add a new list
+PUT http://localhost:8080/api/v1/namespaces/1/lists
+Authorization: Bearer {{auth_token}}
+Content-Type: application/json
+
+{}
+
+###
+
+# Delete a list from a list
+DELETE http://localhost:8080/api/v1/lists/28
+Authorization: Bearer {{auth_token}}
+
+###
+