explicit inheritance of com.amazonaws.AmazonWebServiceClient's methods fo

[xoba]

explicit inheritance of com.amazonaws.AmazonWebServiceClient's methods for all aws service interfaces, like com.amazonaws.services.s3.AmazonS3.

in particular, this exposes the method "addRequestHandler," which is convenient for "requester pays buckets" where
you use a com.amazonaws.handlers.RequestHandler to add the "x-amz-request-payer: requester" header. without this new feature,
one is forced to use class com.amazonaws.services.s3.AmazonS3Client, instead of interface com.amazonaws.services.s3.AmazonS3;
the latter is sort of preferred from basic object-oriented programming principles.

for instance: here's how i now can access a request-pays bucket:

    AmazonS3 s3 = ................;

    s3.addRequestHandler(new AbstractRequestHandler() {
        @Override
        public void beforeRequest(Request<?> request) {
            request.addHeader("x-amz-request-payer", "requester");
            System.out.println("added request payer: " + request);
        }
    });

    for (S3ObjectSummary s : s3.listObjects("commoncrawl-crawl-002").getObjectSummaries()) {
        System.out.println(s.getKey());
    }

[xoba]

after thinking about this a few more days, i think i'm actually satisfied calling the addRequestHandler method on the implementation classes like com.amazonaws.services.s3.AmazonS3Client directly... thus, i'm sort of "cancelling" my pull request.