I'll work on this if thats alright

Hello, I was taking a look at this when I ran into the following technical issue.

The AVL tree should logically be a subclass of the binary search tree as they share common operations (search, traversals). However, this is not possible because the AVL tree's nodes are fundamentally different from the ones used in the basic BST (they need an extra field to store the height of the node).

So my question is this:

Should I implement the AVL tree as a subclass of the binary search tree (changes would need to be made in the file binary_search_tree.hpp) or as a standalone class?