Fix a little typo bug in the S3 tutorial.  Fixes #2087.
Fixed the DDBv2 `has_item` support.

Thanks to dorfsmay for the report!
Merge pull request #2088 from garnaat/fix-2087

Fix a little typo bug in the S3 tutorial.
Merge branch 'ddb2-fix-has-item' into develop
Fixes #2090.