add ap-northeast-2: Asia Pacific (Seoul)

builder/amazon/common/ami_config_test.go

@@ -30,8 +30,8 @@ func TestAMIConfigPrepare_regions(t *testing.T) {
 		t.Fatalf("shouldn't have err: %s", err)
 	}
 
-	c.AMIRegions = []string{"ap-northeast-1", "ap-southeast-1", "ap-southeast-2",
-		"cn-north-1", "eu-central-1", "eu-west-1", "sa-east-1",
+	c.AMIRegions = []string{"ap-northeast-1", "ap-northeast-2", "ap-southeast-1",
+		"ap-southeast-2", "cn-north-1", "eu-central-1", "eu-west-1", "sa-east-1",
 		"us-east-1", "us-gov-west-1", "us-west-1", "us-west-2"}
 	if err := c.Prepare(nil); err != nil {
 		t.Fatalf("shouldn't have err: %s", err)

builder/amazon/common/regions.go

@@ -3,8 +3,9 @@ package common
 // IsValidRegion returns true if the supplied region is a valid AWS
 // region and false if it's not.
 func ValidateRegion(region string) bool {
-	var regions = [11]string{
+	var regions = [12]string{
 		"ap-northeast-1",
+		"ap-northeast-2",
 		"ap-southeast-1",
 		"ap-southeast-2",
 		"cn-north-1",