[7980] Implement item use target requirements store and check (new table item_required_target).

Signed-off-by: VladimirMangos <vladimir@getmangos.com>

* Also implement this table reload
* Static Spell::SendCastResult function for call not from spell code.
  Can be also used in scripts where need send explicitly spell cast error to client.

src/game/World.cpp

@@ -1152,6 +1152,9 @@ void World::SetInitialWorldSettings()
     sLog.outString( "Loading SpellsScriptTarget...");
     spellmgr.LoadSpellScriptTarget();                       // must be after LoadCreatureTemplates and LoadGameobjectInfo
 
+    sLog.outString( "Loading ItemRequiredTarget...");
+    objmgr.LoadItemRequiredTarget();
+
     sLog.outString( "Loading Creature Reputation OnKill Data..." );
     objmgr.LoadReputationOnKill();