* provider/aws: Add Support for maintenance_window and back_window to rds_cluster_instance
Fixes: #9489
```
% make testacc TEST=./builtin/providers/aws TESTARGS='-run=TestAccAWSRDSClusterInstance_basic'
==> Checking that code complies with gofmt requirements...
go generate $(go list ./... | grep -v /terraform/vendor/)
2017/03/28 23:08:45 Generated command/internal_plugin_list.go
TF_ACC=1 go test ./builtin/providers/aws -v -run=TestAccAWSRDSClusterInstance_basic -timeout 120m
=== RUN TestAccAWSRDSClusterInstance_basic
--- PASS: TestAccAWSRDSClusterInstance_basic (1433.41s)
PASS
ok github.com/hashicorp/terraform/builtin/providers/aws 1433.438s
```
* Update rds_cluster_instance.html.markdown
* Update rds_cluster_instance.html.markdown
This test overrides the AWS_DEFAULT_REGION parameter as the security
groups are created in us-east-1 (due to classic VPC requirements)
```
% make testacc TEST=./builtin/providers/aws TESTARGS='-run=TestAccAWSDBSecurityGroup_importBasic'
==> Checking that code complies with gofmt requirements...
go generate $(go list ./... | grep -v /terraform/vendor/)
TF_ACC=1 go test ./builtin/providers/aws -v
-run=TestAccAWSDBSecurityGroup_importBasic -timeout 120m
=== RUN TestAccAWSDBSecurityGroup_importBasic
--- PASS: TestAccAWSDBSecurityGroup_importBasic (49.46s)
PASS
ok github.com/hashicorp/terraform/builtin/providers/aws 49.487s
```
* provider/aws: Support kms_key_id for `aws_rds_cluster`
```
% make testacc TEST=./builtin/providers/aws TESTARGS='-run=TestAccAWSRDSCluster_'
==> Checking that code complies with gofmt requirements...
go generate $(go list ./... | grep -v /terraform/vendor/)
TF_ACC=1 go test ./builtin/providers/aws -v -run=TestAccAWSRDSCluster_
-timeout 120m
=== RUN TestAccAWSRDSCluster_basic
--- PASS: TestAccAWSRDSCluster_basic (127.57s)
=== RUN TestAccAWSRDSCluster_kmsKey
--- PASS: TestAccAWSRDSCluster_kmsKey (323.72s)
=== RUN TestAccAWSRDSCluster_encrypted
--- PASS: TestAccAWSRDSCluster_encrypted (173.25s)
=== RUN TestAccAWSRDSCluster_backupsUpdate
--- PASS: TestAccAWSRDSCluster_backupsUpdate (264.07s)
PASS
ok github.com/hashicorp/terraform/builtin/providers/aws 888.638s
```
* provider/aws: Add KMS Key ID to `aws_rds_cluster_instance`
```
```