MNT: Update mailmap

Author: effigies

.mailmap

@@ -144,6 +144,7 @@ Michael Waskom <michael.l.waskom@gmail.com> <mwaskom@stanford.edu>
 Miguel Molina-Romero <miguel.molina.romero@gmail.com>
 Murat Bilgel <bilgelm@gmail.com> <murat.bilgel@nih.gov>
 Nat Lee <vip3268@gmail.com>
+Ole Numssen <numssen@cbs.mpg.de>
 Oliver Contier <o.contier@gmail.com> <oliver.contier@ovgu.de>
 Olivia Stanley <oliviawstanley@gmail.com>
 Oscar Esteban <code@oscaresteban.es>