Core/Unit: Big cleanup in Unit::CalcAbsorbResist

Core/AuraScript:
	Fix compile time check for AuraScript functions
	Remove AuraApplication from hook functions parameter list, use GetTarget() and GetTargetApplication() instead
	Add OnEffectAbsorb hook
Scripts: move handlers of Spell Deflection, Savage Defense, Primal Tenacity, Nerves of Steel, Astral shift from core to scripts.

--HG--
branch : trunk

src/server/scripts/Spells/spell_dk.cpp

@@ -157,9 +157,49 @@ public:
     }
 };
 
+// 49145 - Spell Deflection
+class spell_dk_spell_deflection : public SpellScriptLoader
+{
+public:
+    spell_dk_spell_deflection() : SpellScriptLoader("spell_dk_spell_deflection") { }
+
+    class spell_dk_spell_deflection_AuraScript : public AuraScript
+    {
+        PrepareAuraScript(spell_dk_spell_deflection_AuraScript);
+
+        uint32 absorbPct;
+        void CalculateAmount(AuraEffect const * /*aurEff*/, int32 & amount, bool & canBeRecalculated)
+        {
+            absorbPct = amount;
+            // Set absorbtion amount to unlimited
+            amount = -1;
+        }
+
+        void Absorb(AuraEffect * /*aurEff*/, DamageInfo & dmgInfo, uint32 & absorbAmount)
+        {
+            // You have a chance equal to your Parry chance
+            if ((dmgInfo.GetDamageType() == DIRECT_DAMAGE) && roll_chance_f(GetTarget()->GetUnitParryChance()))
+                absorbAmount = CalculatePctN(dmgInfo.GetDamage(), absorbPct);
+        }
+
+        void Register()
+        {
+             DoEffectCalcAmount += AuraEffectCalcAmountFn(spell_dk_spell_deflection_AuraScript::CalculateAmount, EFFECT_0, SPELL_AURA_SCHOOL_ABSORB);
+             OnEffectAbsorb += AuraEffectAbsorbFn(spell_dk_spell_deflection_AuraScript::Absorb, EFFECT_0);
+        }
+    };
+
+    AuraScript *GetAuraScript() const
+    {
+        return new spell_dk_spell_deflection_AuraScript();
+    }
+};
+
+
 void AddSC_deathknight_spell_scripts()
 {
     new spell_dk_corpse_explosion();
     new spell_dk_runic_power_feed();
     new spell_dk_scourge_strike();
+    new spell_dk_spell_deflection();
 }