Add Red Black Binary Search Tree

This is a(n):

• New algorithm
• Update to an existing algorithm
• Error
• Proposal to the Repository

Details:

The tree folder is missing Red Black BST data structure. Red Black Binary Search tree is similar to an AVL tree but in this data structure every operation is guaranteed O(clgn), where c is some constant. It is a very important data structure as every operation is really fast and much easier to understand than AVL tree. I would like to add a Red Black BST written in python.