Fix DocumentDB DNS cluster and reader DNS names (#5)

* Fix DocumentDB DNS cluster and reader DNS names

* Update README

* Use `password` from `local`

Author: aknysh

Diff for: README.md

@@ -53,6 +53,11 @@ The module provisions the following resources:
 
 ## Usage
 
+
+**IMPORTANT:** The `master` branch is used in `source` just as an example. In your code, do not pin to `master` because there may be breaking changes between releases.
+Instead pin to the release tag (e.g. `?ref=tags/x.y.z`) of one of our [latest releases](https://github.com/cloudposse/terraform-aws-codefresh-backing-services/releases).
+
+
 ```hcl
 module "codefresh_backing_services" {
   source          = "git::https://github.com/cloudposse/terraform-aws-codefresh-backing-services.git?ref=master"

Diff for: aurora-postgres.tf

@@ -62,7 +62,7 @@ locals {
 }
 
 module "aurora_postgres" {
-  source             = "git::https://github.com/cloudposse/terraform-aws-rds-cluster.git?ref=tags/0.10.0"
+  source             = "git::https://github.com/cloudposse/terraform-aws-rds-cluster.git?ref=tags/0.15.0"
   namespace          = "${var.namespace}"
   stage              = "${var.stage}"
   name               = "${var.name}"
@@ -122,7 +122,7 @@ resource "aws_ssm_parameter" "aurora_postgres_master_username" {
 resource "aws_ssm_parameter" "aurora_postgres_master_password" {
   count       = "${local.postgres_cluster_enabled == "true" ? 1 : 0}"
   name        = "${format(var.chamber_format, local.chamber_service, "aurora_postgres_master_password")}"
-  value       = "${module.aurora_postgres.password}"
+  value       = "${local.postgres_admin_password}"
   description = "Aurora Postgres Password for the master DB user"
   type        = "SecureString"
   key_id      = "${data.aws_kms_key.chamber_kms_key.id}"

Diff for: documentdb.tf

@@ -97,7 +97,7 @@ locals {
 }
 
 module "documentdb_cluster" {
-  source                          = "git::https://github.com/cloudposse/terraform-aws-documentdb-cluster.git?ref=tags/0.1.0"
+  source                          = "git::https://github.com/cloudposse/terraform-aws-documentdb-cluster.git?ref=tags/0.2.0"
   enabled                         = "${local.documentdb_cluster_enabled}"
   namespace                       = "${var.namespace}"
   stage                           = "${var.stage}"
@@ -113,6 +113,8 @@ module "documentdb_cluster" {
   vpc_id                          = "${var.vpc_id}"
   subnet_ids                      = ["${var.subnet_ids}"]
   zone_id                         = "${local.zone_id}"
+  cluster_dns_name                = "docdb-master.${var.name}"
+  reader_dns_name                 = "docdb-replicas.${var.name}"
   allowed_security_groups         = ["${var.security_groups}"]
   apply_immediately               = "${var.documentdb_apply_immediately}"
   enabled_cloudwatch_logs_exports = ["${var.documentdb_enabled_cloudwatch_logs_exports}"]