Summary:
Ref T11801. This makes testing/debugging a little easier.
Also fix some inconsistencies with `importAuthorPHID` handling -- it should be the import's author PHID in all cases, so we update imported events properly.
Test Plan: Imported a French holiday with `bin/calendar reload ...`.
Reviewers: chad
Reviewed By: chad
Maniphest Tasks: T11801
Differential Revision: https://secure.phabricator.com/D16814
