AUTHORS: update from git log

$ git shortlog -s -n

AUTHORS

@@ -1,3 +1,71 @@
-Tambet Ingo  <tambet@gmail.com>
-Dan Williams <dcbw@redhat.com>
-Aleksander Morgado <aleksander@aleksander.es>
+
+Current maintainers:
+  Dan Williams       <dcbw@redhat.com>
+  Aleksander Morgado <aleksander@aleksander.es>
+
+Previous maintainers:
+  Tambet Ingo        <tambet@gmail.com>
+
+Other contributors:
+  Ben Chan
+  Nathan Williams
+  Torgny Johansson
+  Alexander Sack
+  Guido Günther
+  Eric Shienbrood
+  Elly Jones
+  Prathmesh Prabhu
+  Thieu Le
+  Thomas Tuttle
+  Bjørn Mork
+  Marius B. Kotsbak
+  Christian Persch
+  David McCullough
+  Michael Biebl
+  Colin Walters
+  Franko Fang
+  Jason Glasgow
+  Jeroen Elebaut
+  Ori Inbar
+  David Rochberg
+  Jiří Klimeš
+  Martyn Russell
+  Graham Inggs
+  Lionel Landwerlin
+  Martin Pitt
+  Norbert Frese
+  Thomas Bechtold
+  Yegor Yefremov
+  Yunlian Jiang
+  Adrian Bunk
+  Amit Mendapara
+  Andrew Bird
+  Anton Blanchard
+  Arnd Hannemann
+  Arun Raghavan
+  Bryan Duff
+  David (Pololu)
+  David Castellanos
+  David Härdeman
+  Dmitry Ivanyushin
+  Eugene Crosser
+  Evan Nemerson
+  Fangxiaozhi (Franko)
+  Gerald Richter
+  Jens Seidel
+  Julian Oes
+  Jun Woo Lee
+  M. I. Spozta
+  Mario Blättermann
+  Michał Sroczyński
+  Nathan J. Williams
+  Noel J. Bergman
+  Quentin.Li
+  Thomas Grenman
+  Tom Bechtold
+  Tom Goetz
+  Tore Anderson
+  Vincent Untz
+  Vitaly Gimly
+  Yuri Chornoivan
+  kuonirat