Fixed S3 Java files so tests all pass

[scmacdon]

This pull request made fixes to the Java S3 tests so they all pass.

---

By submitting this pull request, I confirm that my contribution is made under the terms of the Apache 2.0 license.

[rlhagerm]

Needs proper handling of required bucket names that will work with the tests. You'll need a way to put a real bucket name for tests, such as: create/destroy the bucket as part of the test, provide the bucket name as a parameter, etc, but not hard-code a non-approved name into any of the actual examples.

[scmacdon]

Results are

Bucket names inside snippet regions: All compliant (amzn-s3-demo- prefix)
No hardcoded credentials
No critical unused imports in the files
All 85 tests passing

[scmacdon]

Here is CD

http://dev-dsk-scmacdon-1d-3bd40994.us-east-1.amazon.com/sos-metadata166/build/AWSCodeExampleUsageDocs/AWSCodeExampleUsageDocs-3.0/AL2_x86_64/DEV.STD.PTHREAD/build/server-root/code-library/latest/ug/what-is-code-library.html