Implement replicaLoadBalancer boolean flag. (#38)

The flag adds a replica service with the name cluster_name-repl and
a DNS name that defaults to {cluster}-repl.{team}.{hostedzone}.

The implementation converted Service field of the cluster into a map
with one or two elements and deals with the cases when the new flag
is changed on a running cluster
(the update and the sync should create or delete the replica service).
In order to pick up master and replica service and master endpoint
when listing cluster resources.

* Update the spec when updating the cluster.

pkg/util/constants/annotations.go

@@ -1,5 +1,6 @@
 package constants
 
+// Names and values in Kubernetes annotation for services, statefulsets and volumes
 const (
 	ZalandoDNSNameAnnotation           = "external-dns.alpha.kubernetes.io/hostname"
 	ElbTimeoutAnnotationName           = "service.beta.kubernetes.io/aws-load-balancer-connection-idle-timeout"

pkg/util/constants/aws.go

@@ -2,8 +2,11 @@ package constants
 
 import "time"
 
+// AWS specific constants used by other modules
 const (
-	AWS_REGION       = "eu-central-1"
+	// default region for AWS. TODO: move it to the operator configuration
+	AWS_REGION = "eu-central-1"
+	// EBS related constants
 	EBSVolumeIDStart = "/vol-"
 	EBSProvisioner   = "kubernetes.io/aws-ebs"
 	//https://docs.aws.amazon.com/AWSEC2/latest/APIReference/API_VolumeModification.html

pkg/util/constants/kubernetes.go

@@ -2,6 +2,7 @@ package constants
 
 import "time"
 
+// General kubernetes-related constants
 const (
 	ListClustersURITemplate     = "/apis/" + TPRVendor + "/" + TPRApiVersion + "/namespaces/%s/" + ResourceName       // Namespace
 	WatchClustersURITemplate    = "/apis/" + TPRVendor + "/" + TPRApiVersion + "/watch/namespaces/%s/" + ResourceName // Namespace

pkg/util/constants/thirdpartyresource.go

@@ -1,5 +1,6 @@
 package constants
 
+// Different properties of the PostgreSQL Third Party Resources
 const (
 	TPRName        = "postgresql"
 	TPRVendor      = "acid.zalan.do"

pkg/util/constants/units.go

@@ -1,5 +1,6 @@
 package constants
 
+// Measurement-unit definitions
 const (
 	Gigabyte = 1073741824
 )