Update .mailmap with even more info from xmonad-contrib

The lesson here is that stuff like this should not be done manually.
For future reference, here's the machinery I ended up using:

    https://gist.github.com/7b78eba396024d4f56fa217867e2a3a8

.mailmap

@@ -2,14 +2,17 @@ Adam Plaice <plaice.adam+github@gmail.com>
 Brandon S Allbery KF8NH <allbery.b@gmail.com>
 Brent Yorgey <byorgey@gmail.com> <byorgey@cis.upenn.edu>
 Conrad Irwin <conrad.irwin@gmail.com>
+Daniel Neri <daniel.neri@sigicom.com> <daniel.neri@sigicom.se>
 Daniel Schoepe <daniel.schoepe@gmail.com> <asgaroth_@gmx.de>
 Daniel Wagner <me@dmwit.com> <daniel@wagner-home.com>
 David Glasser <glasser@mit.edu>
 Deven Lahoti <deven.lahoti@gmail.com>
+Devin Mullins <devin.mullins@gmail.com> <me@twifkak.com>
 Don Stewart <dons00@gmail.com> <dons@cse.unsw.edu.au>
 Don Stewart <dons00@gmail.com> <dons@galois.com>
+Felix Springer <felixspringer149@gmail.com> <39434424+jumper149@users.noreply.github.com>
 Gwern Branwen <gwern@gwern.net> <gwern0@gmail.com>
-Lukas Mai <l.mai@web.de> <l.mai@web.de>
+Lukas Mai <l.mai@web.de>
 Marshall Lochbaum <mwlochbaum@gmail.com>
 Michael G. Sloan <mgsloan@gmail.com>
 Neil Mitchell <ndmitchell@gmail.com> <http://www.cs.york.ac.uk/~ndm/>
@@ -23,7 +26,13 @@ Robert Marlow <bobstopper@bobturf.org>
 Robert Marlow <bobstopper@bobturf.org> <robreim@bobturf.org>
 Sam Hughes <hughes@rpi.edu>
 Shae Erisson <shae@ScannedInAvian.com>
+Sibi Prabakaran <sibi@psibi.in>
+Sibi Prabakaran <sibi@psibi.in> <psibi2000@gmail.com>
 Spencer Janssen <spencerjanssen@gmail.com> <sjanssen@cse.unl.edu>
 Timothy Hobbs <tim.thelion@gmail.com>
+Tomas Janousek <tomi@nomi.cz>
+Valery V. Vorotyntsev <valery.vv@gmail.com>
 Vanessa McHale <vamchale@gmail.com> <vanessa.mchale@reconfigure.io>
 Wirt Wolff <wirtwolff@gmail.com>
+
+slotThe <soliditsallgood@mailbox.org> <50166980+slotThe@users.noreply.github.com>