Tidy up.
Tidy up.
Remove unused code.
Replace polymorphism with pattern matching.
Remove unused code.
Tidy up.
Remove unused code.
Replace polymorphism with pattern matching.
Tidy up.
Some code for removeL.
Red black tree?
Remove key.  Compare on count.
TestVolumeTree
Insertion working.
Updates working.
Remove unused overwrite parameter.
Fix some issues with doRange.
Fix bug in range method.
Remove debugging.
Fix delete.