Core: Some optimizations

- Declare some functions const
- Fix some mem leak
- Fix some resource leak
- Remove unused variables and functions
- Remove duplicate functions
- Reduce the scope of some variables
- Remove unused file

--HG--
branch : trunk

src/server/game/Skills/SkillExtraItems.cpp

@@ -52,8 +52,6 @@ SkillExtraItemMap SkillExtraItemStore;
 // loads the extra item creation info from DB
 void LoadSkillExtraItemTable()
 {
-    uint32 count = 0;
-
     SkillExtraItemStore.clear();                            // need for reload
 
     //                                                 0        1                       2                       3
@@ -61,6 +59,8 @@ void LoadSkillExtraItemTable()
 
     if (result)
     {
+        uint32 count = 0;
+
         barGoLink bar(result->GetRowCount());
 
         do