[Feature] Change mana_used to int32 (#2321)

* Changed mana_used to use int32,
to match int32 mana_cost
This will allow higher mana costs to function

* Corrected DoHPToManaCovert to Int32

* Removed unused uint16 GetMana function call from Server/zone/questmgr.h

* Change GetSkillDmgAmt from Int16 to Int32 (SkillDamageAmount2 which uses function is Int32)

* Delete mob.cpp

* Revert "Delete mob.cpp"

This reverts commit 3db8bf04d1.

* Revert "Change GetSkillDmgAmt from Int16 to Int32 (SkillDamageAmount2 which uses function is Int32)"

This reverts commit cf5dbc9ce8.

Co-authored-by: dmcintosh-BCT <dan@blackcreektechnologies.com>

zone/questmgr.h

@@ -354,7 +354,6 @@ public:
 	bool createBot(const char *name, const char *lastname, uint8 level, uint16 race, uint8 botclass, uint8 gender);
 #endif
 
-	inline uint16 GetMana(uint32 spell_id) { return( spells[spell_id].mana); }
 
 private:
 	std::stack<running_quest> quests_running_;