Tweaked the main method in the check digit generator to make it slightly
easier to use on the command line.
First attempt at unit test for work contributor visibility rules.
Updated unit test for work contributor visibility so that contributor
email should never be returned by API.
Updated so that all work contributor visibility unit tests pass.
Added script for migrating existing contributors stored as JSON in DB
(checks contributor name visibility).
Merge pull request #603 from ORCID/fixContributorVisibility

Fix contributor visibility