Adding sa-east-1 region.

Author: wikka

src/main/java/org/elasticsearch/cloud/aws/AwsS3Service.java

@@ -121,6 +121,10 @@ public synchronized AmazonS3 client() {
                 endpoint = "s3-eu-west-1.amazonaws.com";
             } else if ("eu-west-1".equals(region)) {
                 endpoint = "s3-eu-west-1.amazonaws.com";
+            } else if ("sa-east".equals(region)) {
+                endpoint = "s3-sa-east-1.amazonaws.com";
+            } else if ("sa-east-1".equals(region)) {
+                endpoint = "s3-sa-east-1.amazonaws.com";
             } else {
                 throw new ElasticSearchIllegalArgumentException("No automatic endpoint could be derived from region [" + region + "]");
             }