Handling new versions of the bulletins

[egrimshaw]

This issue happens rarely.

If a user were to accidentally upload a late version of a bulletin (ex: version 2) and then try to upload an older version (ex: version 1), the database would not update.

Because of this, the user will not be able to make a call to U-3 for version 1 and 2 (find changes in vulnerabilities between version x and version y of a certain bulletin) as the database will never have stored version 1.