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/scripts/Northrend/Naxxramas/boss_gothik.cpp

@@ -384,7 +384,7 @@ public:
 
         void UpdateAI(const uint32 diff)
         {
-            if (!UpdateCombatState() || !CheckInRoom())
+            if (!UpdateVictim() || !CheckInRoom())
                 return;
 
             events.Update(diff);

src/server/scripts/Northrend/Naxxramas/boss_kelthuzad.cpp

@@ -377,7 +377,7 @@ public:
 
         void UpdateAI(const uint32 diff)
         {
-            if (!UpdateCombatState())
+            if (!UpdateVictim())
                 return;
 
             events.Update(diff);

src/server/scripts/Northrend/Naxxramas/boss_noth.cpp

@@ -142,7 +142,7 @@ public:
 
         void UpdateAI(const uint32 diff)
         {
-            if (!UpdateCombatState() || !CheckInRoom())
+            if (!UpdateVictim() || !CheckInRoom())
                 return;
 
             events.Update(diff);

src/server/scripts/Northrend/Naxxramas/boss_sapphiron.cpp

@@ -228,7 +228,7 @@ public:
 
             events.Update(diff);
 
-            if ((phase != PHASE_BIRTH && !UpdateCombatState()) || !CheckInRoom())
+            if ((phase != PHASE_BIRTH && !UpdateVictim()) || !CheckInRoom())
                 return;
 
             if (CanTheHundredClub)