Update README with deletion notes
Eliminate empty returns in traversals
Add simple tests for rebalance method
Fix test for right rotation
Adjust balance method to properly handle cases where tree has only one branch
Implement additional tests for rebalance and insertion/deletion with rebalance
Remove unnecessary import
Implement rebalance, fix rotations, add rebalance to insert & delete
Update README
Merge pull request #20 from MikeDelaney/avl

Avl