Using detection confidence from other detector

[rose-jinyang]

Hello How are you? Thanks for contributing to this project. This project shows a simple explanation in combining this tracker with other detector. But I think that the detailed detector specification is needed to combine with this tracker. That's because a general detector filters objects with confidences lower than a certain threshold in post-processing like NMS. I found that this tracker uses a high threshold and a low threshold for detection confidence. I think that the logic using confidences in a detector and this tracker should be consistent.