Modernize various files (part 2)

* range-based for loops
* emplace_back instead of push_back
* code style
* C++ headers instead of C headers
* Default operators
* empty stl function

src/inventory.h

@@ -172,7 +172,7 @@ class InventoryList
 {
 public:
 	InventoryList(const std::string &name, u32 size, IItemDefManager *itemdef);
-	~InventoryList();
+	~InventoryList() = default;
 	void clearItems();
 	void setSize(u32 newsize);
 	void setWidth(u32 newWidth);