Add ClusterCreateTime to Redshift response

Fixes #1778

moto/redshift/models.py

@@ -78,6 +78,7 @@ class Cluster(TaggableResourceMixin, BaseModel):
         super(Cluster, self).__init__(region_name, tags)
         self.redshift_backend = redshift_backend
         self.cluster_identifier = cluster_identifier
+        self.create_time = iso_8601_datetime_with_milliseconds(datetime.datetime.now())
         self.status = 'available'
         self.node_type = node_type
         self.master_username = master_username
@@ -237,6 +238,7 @@ class Cluster(TaggableResourceMixin, BaseModel):
                 "Address": self.endpoint,
                 "Port": self.port
             },
+            'ClusterCreateTime': self.create_time,
             "PendingModifiedValues": [],
             "Tags": self.tags,
             "IamRoles": [{

tests/test_redshift/test_redshift.py

@@ -1,5 +1,7 @@
 from __future__ import unicode_literals
 
+import datetime
+
 import boto
 import boto3
 from boto.redshift.exceptions import (
@@ -32,6 +34,8 @@ def test_create_cluster_boto3():
         MasterUserPassword='password',
     )
     response['Cluster']['NodeType'].should.equal('ds2.xlarge')
+    create_time = response['Cluster']['ClusterCreateTime']
+    create_time.should.be.lower_than(datetime.datetime.now(create_time.tzinfo))
 
 
 @mock_redshift