Remove authors from pdf properties when in review mode

[AnkeAnke]

Right now, documents submitted for review carry the authors' names in the pdf properties (assuming that \author is set, which most authors will do). That heavily subverts double-blindness.

This fix replaces the author property with anonymous authors when review mode is set.

[codydunne]

This looks appropriate and is an important change to make before the template is used again.