Suggestion of program update tensorflow 2 changes

[Ry3yr]

Tensorflow 2 introduced massive changes - which cause certain features in the current openmmd implementation to break

tf.app.flags (used in ../src/predict_3dpose.py) is now entirely deprecated.

Usage of

argparse is advised...

See also:
#43

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Currently
tensorflow-1.6.0-cp36-cp36m-win_amd64.whl
and
opencv_python-3.4.10.37-cp36-cp36m-win_amd64.whl
(Might require virtual studio 2022 for installation)

were the key to making this run (Win11)

The two popular ways are:
A) Anaconda Prompt: https://www.youtube.com/watch?v=uZcR1iTPNPs
B) cmd virt env: https://www.youtube.com/watch?v=_JXd41qVfBY