**Is your feature request related to a problem? Please describe.** There is https://github.com/doganoo/PHPAlgorithms/blob/master/src/Datastructure/Graph/Tree/AVLTree/Node.php and https://github.com/doganoo/PHPAlgorithms/blob/master/src/Datastructure/Graph/Tree/AVLTree.php which are not implemented fully yet (buggy). **Describe the solution you'd like** implement AVLTree and write tests
Is your feature request related to a problem? Please describe.
There is https://github.com/doganoo/PHPAlgorithms/blob/master/src/Datastructure/Graph/Tree/AVLTree/Node.php and https://github.com/doganoo/PHPAlgorithms/blob/master/src/Datastructure/Graph/Tree/AVLTree.php which are not implemented fully yet (buggy).
Describe the solution you'd like
implement AVLTree and write tests