shared_ptr -> std::shared_ptr

This is one of the first commits in a plan to remove all `using namespace std;` lines in the entire codebase as it is considered anti-pattern today.

Minecraft.Client/Common/Tutorial/TakeItemHint.h

@@ -15,5 +15,5 @@ public:
 	TakeItemHint(eTutorial_Hint id, Tutorial *tutorial, int items[], unsigned int itemsLength);
 	~TakeItemHint();
 
-	virtual bool onTake( shared_ptr<ItemInstance> item );
+	virtual bool onTake( std::shared_ptr<ItemInstance> item );
 };