Progress updating to cv981/pv973:

* Implemented the new client AND protocol version methods.
* Implemented the new speed laws added in cv980 (http://www.tibia.com/news/?subtopic=newsarchive&id=2251).
* Added more missing bytea to login packets (client version/type and some unknown bytes).
* Fixed the InputMessage::getDouble method.
* Cleaned up some of the const values.
* Started on the pending state features.

TODO:
* Pending game state feature.
* Ensure version compatibility hasn't been compromised.

modules/gamelib/game.lua

@@ -50,8 +50,16 @@ function g_game.getSupportedProtocols()
   return {
     810, 853, 854, 860, 861, 862, 870,
     910, 940, 944, 953, 954, 960, 961,
-    963, 970, 971, 980, 981
+    963, 970, 971, 973
   }
 end
 
+function g_game.getSupportedClients(protocol)
+  clients = {
+    [971] = {980},
+    [973] = {981}
+  }
+  return clients[protocol] or {protocol}
+end
+
 g_game.setRsa(OTSERV_RSA)