There should be some way to turn off the fmt print prompt

Your bptree is so cool !! However, I found some needless fmt.Printf, while it made some interference in my project:

[INFO]11:10:53 Read table finish attach user
[2]1 ->
Leaf [2 3] ->
[INFO]11:10:53 maga

There should be some way to turn off the fmt print prompt I think )

I will pull a small PR if you like