Fixup example documentation for region constants

Fixes aws#557 by removing out dated example documentation from the SDK's
endpoints package and README. The feature to enumerate regions and
services was removed in aws#512 pending further design and development of
service specific endpoint metadata.

README.md

@@ -65,7 +65,7 @@ func main() {
 	}
 
 	// Set the AWS Region that the service clients should use
-	cfg.Region = endpoints.UsWest2RegionID
+	cfg.Region = "us-west-2"
 
 	// Using the Config value, create the DynamoDB client
 	svc := dynamodb.New(cfg)

aws/endpoints/doc.go

@@ -7,30 +7,6 @@
 // endpoint if one is found. The default resolver will search all partitions
 // known by the SDK. e.g AWS Standard (aws), AWS China (aws-cn), and
 // AWS GovCloud (US) (aws-us-gov).
-// .
-//
-// Enumerating Regions and Endpoint Metadata
-//
-// Casting the Resolver returned by DefaultResolver to a EnumPartitions interface
-// will allow you to get access to the list of underlying Partitions with the
-// Partitions method. This is helpful if you want to limit the SDK's endpoint
-// resolving to a single partition, or enumerate regions, services, and endpoints
-// in the partition.
-//
-//     resolver := endpoints.NewDefaultResolver()
-//     partitions := resolver.Partitions()
-//
-//     for _, p := range partitions {
-//         fmt.Println("Regions for", p.ID())
-//         for id, _ := range p.Regions() {
-//             fmt.Println("*", id)
-//         }
-//
-//         fmt.Println("Services for", p.ID())
-//         for id, _ := range p.Services() {
-//             fmt.Println("*", id)
-//         }
-//     }
 //
 // Using Custom Endpoints
 //

doc.go

@@ -43,7 +43,7 @@ SDK's Amazon DynamoDB client.
 		}
 
 		// Set the AWS Region that the service clients should use
-		cfg.Region = endpoints.UsWest2RegionID
+		cfg.Region = "us-west-2"
 
 		// Using the Config value, create the DynamoDB client
 		svc := dynamodb.New(cfg)