Skip fake change messages
Add MultipleInheritanceException
PLFM-1616 Add a worker to sync RDS and DynamoDb periodically
Fix incorrect error message
Merge pull request #268 from eric-wu/develop

Add a worker to sync RDS and DynamoDb periodically and other trivial improvements
Improved schema descriptions in Submission.json
Switched LEFT JOIN to INNER JOIN in SubmissionDAO
PLFM-1667: Fix userID handling for Competition Services