Enroll an Existing User as Reviewer in Add Reviewer should allow search by email and/or login

If you’re trying to enroll an existing user via the Add Reviewer form, it only allows you to search by name, which is a pretty big issue in an installation with multiple journals, since it’s pretty common to have different people with the same name or even a person with multiple accounts.

To solve this, it should either allow searching using other options such as email account or login, or at least display the email account or login next to the possible reviewer’s name.