incorrect spelling of height. (williamfiset#307)

Changed the spelling of hieght to height.

Author: swu2050

src/main/java/com/williamfiset/algorithms/datastructures/balancedtree/AVLTreeRecursive.java

@@ -253,7 +253,7 @@ private Node remove(Node node, T elem) {
         // successor of the node being removed can either be the largest
         // value in the left subtree or the smallest value in the right
         // subtree. As a heuristic, I will remove from the subtree with
-        // the greatest hieght in hopes that this may help with balancing.
+        // the greatest height in hopes that this may help with balancing.
       } else {
 
         // Choose to remove from left subtree