Group S3 options by source

I am trying to group the S3 options by source:

- sqs queue
- bucket
  - aws bucket arn
  - non-aws bucket name

With this approach, we can define shared options like
`number_of_workers` only once. This should streamline the options and
avoid duplicated definitions.

packages/aws_logs/data_stream/generic/agent/stream/aws-s3.yml.hbs

@@ -4,57 +4,54 @@ data_stream:
 pipeline: {{pipeline}}
 {{/if}}
 
+{{! The aws-s3 input can be configured to read from an SQS queue or an S3 bucket. }}
+
+{{! start SQS queue }}
 {{#unless bucket_arn}}
 {{#unless non_aws_bucket_name}}
 {{#if queue_url }}
 queue_url: {{ queue_url }}
 {{/if}}
 {{/unless}}
 {{/unless}}
+{{! end SQS queue }}
 
-{{#unless queue_url}}
-{{#unless non_aws_bucket_name}}
-{{#if bucket_arn }}
-bucket_arn: {{ bucket_arn }}
-{{/if}}
+{{#unless queue_url}}{{! start S3 bucket }}
+
+{{!
+When using an S3 bucket, you can specify only one of the following options:
+- An AWS bucket ARN
+- A non-AWS bucket name
+}}
+
+{{! shared S3 options }}
 {{#if number_of_workers }}
 number_of_workers: {{ number_of_workers }}
 {{/if}}
+
+{{#if bucket_list_prefix }}
+bucket_list_prefix: {{ bucket_list_prefix }}
+{{/if}}
+
 {{#if bucket_list_interval }}
 bucket_list_interval: {{ bucket_list_interval }}
 {{/if}}
-{{/unless}}
+
+{{! AWS S3 bucket ARN options }}
+{{#unless non_aws_bucket_name}}
+{{#if bucket_arn }}
+bucket_arn: {{ bucket_arn }}
+{{/if}}
 {{/unless}}
 
+{{! non-AWS S3 bucket ARN options }}
 {{#unless bucket_arn}}
-{{#unless queue_url}}
 {{#if non_aws_bucket_name }}
 non_aws_bucket_name: {{ non_aws_bucket_name }}
 {{/if}}
-{{#if number_of_workers }}
-number_of_workers: {{ number_of_workers }}
-{{/if}}
-{{#if bucket_list_interval }}
-bucket_list_interval: {{ bucket_list_interval }}
-{{/if}}
-{{/unless}}
 {{/unless}}
 
-{{#unless queue_url}}
-{{#unless non_aws_bucket_name}}
-{{#unless bucket_arn }}
-{{#if bucket_list_prefix }}
-bucket_list_prefix: {{ bucket_list_prefix }}
-{{/if}}
-{{#if number_of_workers }}
-number_of_workers: {{ number_of_workers }}
-{{/if}}
-{{#if bucket_list_interval }}
-bucket_list_interval: {{ bucket_list_interval }}
-{{/if}}
-{{/unless}}
-{{/unless}}
-{{/unless}}
+{{/unless}}{{! end S3 bucket }}
 
 {{#if buffer_size }}
 buffer_size: {{ buffer_size }}