Updae list of authors

.mailmap

@@ -3,3 +3,4 @@ Richo Healey <richo@psych0tik.net>
 Xavier Delannoy <xavier.delannoy@gmail.com>
 Christian Boos <cboos@edgewall.org> <cboos@bct-technology.com>
 Martin Lenders <mlenders@elegosoft.com> <authmill@datalove.me>
+Xu Tao <xutao@douban.com>

README.rst

@@ -53,13 +53,14 @@ This is the list of authors of pygit2, sorted by number of commits (as shown by
 - W Trevor King
 - Dave Borowitz
 - Carlos Martín Nieto
+- Richo Healey
 - Christian Boos
 - Julien Miotte
-- Richo Healey
 - Martin Lenders
 - Xavier Delannoy
 - Yonggang Luo
 - Valentin Haenel
+- Bernardo Heynemann
 - John Szakmeister
 - David Versmisse
 - Petr Hosek
@@ -68,7 +69,10 @@ This is the list of authors of pygit2, sorted by number of commits (as shown by
 - Petr Viktorin
 - Alex Chamberlain
 - Amit Bakshi
+- Andrey Devyatkin
 - Ben Davis
+- Daniel Rodríguez Troitiño
+- Hervé Cauwelier
 - Jared Flatow
 - Sarath Lakshman
 - Vicent Marti
@@ -82,11 +86,13 @@ This is the list of authors of pygit2, sorted by number of commits (as shown by
 - Eric Schrijver
 - Erik van Zijst
 - Ferengee
+- Fraser Tweedale
 - Hugh Cole-Baker
 - Josh Bleecher Snyder
 - Jun Omae
 - Ridge Kennedy
 - Rui Abreu Ferreira
+- Xu Tao
 - pistacchio