Add more methods to SpellScript.

Spells cleanup: move spells from the core to scripts.

* Shaman spells: 39610 Mana Tide Totem, 1535 Fire Nova (and ranks)
* Death Knight spells: 55090 Scourge Strike (and ranks), 49158 Corpse Explosion (and ranks), 50524 Runic Power Feed
* Druid spells: 54846 Glyph of Starfire
* Warlock spells: 6201 Create Healthstone (and ranks), 47422 Everlasting Affliction, 47193 Demonic Empowerment, 63521 Guarded by The Light
* Hunter spells: 37506 Scatter Shot, 53412 Invigoration, 53209 Chimera Shot
* Quest spells: 45449 Arcane Prisoner Rescue (quest 11587), 46023 The Ultrasonic Screwdriver (quest 11730). Closes issue #3068

Clean old code for hunter's Heart of the Phoenix, move script effect of hunter's Master's Call to corresponding script.
Move DK's Hungering Cold to spell_scripts table (needs DB support)

--HG--
branch : trunk

src/server/game/Spells/SpellScript.h

@@ -155,6 +155,12 @@ class SpellScript : public _SpellScript
 
         // method avalible only in EffectHandler method
         int32 GetEffectValue();
+
+        // returns: cast item if present.
+        Item * GetCastItem();
+
+        // Creates item. Calls Spell::DoCreateItem method.
+        void CreateItem(uint32 effIndex, uint32 itemId);
 };
 // SpellScript interface
 //