Migrated from tensorflow v1 to tensorflow v2 and updated requirements.

[githubharald]

Hi,

thanks for your contribution, making the code compatible with TF2 is a good idea. However, the script (python main.py ) crashes with your modifications because the method inferBatch must return a tuple of length 2 (second value is the probability).

Please correct this, then I will merge your changes.

Best Harald

[n1snt]

I have fixed the issue which was causing the above mentioned problem.

[githubharald]

merged it. thank you.