Improve player model credits, add contributors to license (#2741)

mods/player_api/README.txt

@@ -13,13 +13,11 @@ Various Minetest developers and contributors (LGPLv2.1+)
 
 Authors of media (textures, models and sounds)
 ----------------------------------------------
-stujones11 (CC BY-SA 3.0):
+Original model by MirceaKitsune (CC BY-SA 3.0).
+Various alterations and fixes by kilbith, sofar, xunto, Rogier-5, TeTpaAka, Desour,
+stujones11, An0n3m0us (CC BY-SA 3.0):
   character.b3d
-  character.blend -- Both derived from a model by MirceaKitsune (CC BY-SA 3.0)
-
-An0n3m0us (CC BY-SA 3.0):
-  character.b3d
-  character.blend -- Player animation improvement
+  character.blend
 
 Jordach (CC BY-SA 3.0):
   character.png

mods/player_api/license.txt

@@ -2,8 +2,8 @@ License of source code
 ----------------------
 
 GNU Lesser General Public License, version 2.1
-Copyright (C) 2011-2018 celeron55, Perttu Ahola <celeron55@gmail.com>
-Copyright (C) 2011-2018 Various Minetest developers and contributors
+Copyright (C) 2011 celeron55, Perttu Ahola <celeron55@gmail.com>
+Copyright (C) 2011 Various Minetest developers and contributors
 
 This program is free software; you can redistribute it and/or modify it under the terms
 of the GNU Lesser General Public License as published by the Free Software Foundation;
@@ -19,8 +19,15 @@ Licenses of media (textures, models and sounds)
 -----------------------------------------------
 
 Attribution-ShareAlike 3.0 Unported (CC BY-SA 3.0)
-Copyright (C) 2011-2018 celeron55, Perttu Ahola <celeron55@gmail.com>
-Copyright (C) 2012-2018 Jordach
+Copyright (C) 2011 celeron55, Perttu Ahola <celeron55@gmail.com>
+Copyright (C) 2012 MirceaKitsune
+Copyright (C) 2012 Jordach
+Copyright (C) 2015 kilbith
+Copyright (C) 2016 sofar
+Copyright (C) 2016 xunto
+Copyright (C) 2016 Rogier-5
+Copyright (C) 2017 TeTpaAka
+Copyright (C) 2017 Desour
 Copyright (C) 2018 stujones11
 Copyright (C) 2019 An0n3m0us