Merge pull request #2239 from mattray/regions

Updated GCP regions based on "gcloud compute regions list" output

pkg/cloud/gcp/provider.go

@@ -67,18 +67,28 @@ var gcpRegions = []string{
 	"australia-southeast2",
 	"europe-central2",
 	"europe-north1",
+	"europe-southwest1",
 	"europe-west1",
+	"europe-west10",
+	"europe-west12",
 	"europe-west2",
 	"europe-west3",
 	"europe-west4",
 	"europe-west6",
+	"europe-west8",
 	"europe-west9",
+	"me-central1",
+	"me-central2",
+	"me-west1",
 	"northamerica-northeast1",
 	"northamerica-northeast2",
 	"southamerica-east1",
+	"southamerica-west1",
 	"us-central1",
 	"us-east1",
 	"us-east4",
+	"us-east5",
+	"us-south1",
 	"us-west1",
 	"us-west2",
 	"us-west3",