Upload User Manager by name or user name in Kickstarter template

[#1]

When bulk uploading Users using a Kickstarter template, I am unable to upload the Users' Managers because the template requires the Managers' IDs. We may already be uploading the Managers at the same time and won't have their WF Manager IDs but DO have their name and email address/user name. It would be very useful to be able to set up the User-Manager relationship during the bulk upload.