Merge pull request #2041 from jasongrout/mailmap3

Add Doug Redden to mailmap

.mailmap

@@ -28,6 +28,7 @@ David P. Sanders <dpsanders@gmail.com> David P. Sanders <dpsanders@ciencias.unam
 David Warde-Farley <wardefar@iro.umontreal.ca> David Warde-Farley <>
 Di Wang <orpheus92@sci.utah.edu> Di <orpheus92@sci.utah.edu>
 Doug Blank <dblank@cs.brynmawr.edu> Doug Blank <doug.blank@gmail.com>
+Doug Redden <doug.redden@gmail.com> DougRzz <doug.redden@gmail.com>
 Eugene Van den Bulke <eugene.van-den-bulke@gmail.com> Eugene Van den Bulke <eugene.vandenbulke@gmail.com> 
 Evan Patterson <epatters@enthought.com> <epatters@EPattersons-MacBook-Pro.local>
 Evan Patterson <epatters@enthought.com> <epatters@evan-laptop.localdomain>