Replace hardcoded client(100) and server side (255) level limtation values by defines.

(cherry picked from commit 389a1784e288f11587067d3a6d4b70cce9214cb9)

Conflicts:

	src/game/Player.cpp
	src/game/World.cpp
	src/shared/Database/DBCStructure.h

src/shared/Database/DBCStructure.h

@@ -267,6 +267,7 @@ struct GemPropertiesEntry
     uint32      color;
 };
 
+// All Gt* DBC store data for 100 levels, some by 100 per class/race
 #define GT_MAX_LEVEL    100
 
 struct GtCombatRatingsEntry