Replace with opencv NMS

This version replaces the original hard-coded NMS with the opencv cv2.dnn.NMSBoxes method.
This simplifies the code and improve portability to other programing languages.
Performance-wise it is similar to potentially slightly faster.
The function signature is the same except the default scoreThreshold is now 0.5

Other changes:

• the method in MTM.NMS PointInRect and computeIoU have been removed (not used anymore for NMS)
• tutorials updated with timeit benchmarks

Improve versioning

• don't mention any opencv in setup.py (more flexible installation)
• Define MTM version in a single place

Add computeScoreMap method

Add new convenient method computeScoreMap
No other change, no backward compatibility issue

Autocast 16-bit images to 32-bit for matchTemplate

OpenCV match template only support 8-bit or 16-bit images
In Multi-template matching, if both the images and template are 8-bit then the function matchTemplate is called as such.
In all other cases, the template and image are casted to 32-bit to call matchTemplate.

Use pandas for hits

1.5.1

fix formating

Add drawBoxesOnRGB

Add methods:

• drawBoxesOnRGB
• drawBoxesOnGray

Removed:

• drawBoxes

Ie clearer what the function produce
drawBoxesOnGray can be used to make mask for instance

Minor improvements

• format docstring in numpy style
• Improve doc in the readme
• drawBoxes now output a RGB image (initial grayscale image are duplicated as RGB)

Initial stable release

Stable release at time of publication