fix 3.0.1 config generation

[motobob]

closes #450

[motobob]

1> rp(erlcloud_aws:auto_config()).                        
{ok,#aws_config{as_host = "autoscaling.us-west-2.amazonaws.com",
                ec2_host = "ec2.us-west-2.amazonaws.com",
                iam_host = "iam.amazonaws.com",
                sts_host = "sts.us-west-2.amazonaws.com",
                s3_scheme = "https://",
                s3_host = "s3-us-west-2.amazonaws.com",s3_port = 80,
                s3_follow_redirect = false,s3_follow_redirect_count = 2,
                s3_bucket_access_method = vhost,
                s3_bucket_after_host = false,
                sdb_host = "sdb.us-west-2.amazonaws.com",
                elb_host = "elasticloadbalancing.us-west-2.amazonaws.com",
                rds_host = "rds.us-west-2.amazonaws.com",
                ses_host = "email.us-west-2.amazonaws.com",
                sqs_host = "sqs.us-west-2.amazonaws.com",
                sqs_protocol = undefined,sqs_port = undefined,
                emr_scheme = "https://",
                emr_host = "elasticmapreduce.us-west-2.amazonaws.com",
                emr_port = undefined,sns_scheme = "http://",
                sns_host = "sns.us-west-2.amazonaws.com",
                mturk_host = "mechanicalturk.amazonaws.com",
                mon_host = "monitoring.amazonaws.com",mon_port = undefined,
                mon_protocol = undefined,ddb_scheme = "https://",
                ddb_host = "dynamodb.us-west-2.amazonaws.com",ddb_port = 80,
                ddb_retry = #Fun<erlcloud_ddb_impl.retry.1>,
                ddb_streams_scheme = "https://",
                ddb_streams_host = "streams.dynamodb.us-west-2.amazonaws.com",
                ddb_streams_port = 80,route53_scheme = "https://",
                route53_host = "route53.amazonaws.com",route53_port = "80",
                lambda_scheme = "https://",
                lambda_host = "lambda.us-west-2.amazonaws.com",
                lambda_port = 443,redshift_scheme = "https://",
                redshift_host = "redshift.us-west-2.amazonaws.com",
                redshift_port = 443,kinesis_scheme = "https://",
                kinesis_host = "kinesis.us-west-2.amazonaws.com",
                kinesis_port = 80,
                kinesis_retry = #Fun<erlcloud_kinesis_impl.retry.2>,
                glue_scheme = "https://",
                glue_host = "glue.us-west-2.amazonaws.com",glue_port = 443,
                athena_scheme = "https://",
                athena_host = "athena.us-west-2.amazonaws.com",
                athena_port = 443,kms_scheme = "https://",