fails when a contributor is a string instead of an object. see https://github.com/jonschlinkert/sync-pkg/commit/67dc6c8f94fa5db2d8dc902f3491bac03b607261#diff-8191924d78e7652d71643c49ac2716c8R69
fails when a contributor is a string instead of an object.
see jonschlinkert/sync-pkg@67dc6c8#diff-8191924d78e7652d71643c49ac2716c8R69