[Quest API] Add RemoveAlternateCurrencyValue() to Perl/Lua (#4190)

# Perl
- Add `$client->RemoveAlternateCurrencyValue(currency_id, amount)`.

# Lua
- Add `client:RemoveAlternateCurrencyValue(currency_id, amount)`.

# Notes
- Allows operators to more easily remove alternate currencies, returns a `bool`, `false` if failed`, `true` if succeeded.
- Added `Zone::DoesAlternateCurrencyExist` that will reject setting, removing, or adding  to a currency that does not exist.

zone/lua_client.h

@@ -567,6 +567,7 @@ public:
 	void CampAllBots();
 	void CampAllBots(uint8 class_id);
 	bool RemoveAAPoints(uint32 points);
+	bool RemoveAlternateCurrencyValue(uint32 currency_id, uint32 amount);
 
 	void DialogueWindow(std::string markdown);