feat: add 2 new rotation flags in the ocr_predictor

[charlesmindee]

This PR adds the 2 flags introduced in #551 in the highest level predictor so the user can easily choose the parameters of the rotation.

Any feedback is welcome!

[codecov]

Codecov Report

Merging #632 (1c1a2c3) into main (16d842e) will increase coverage by 0.02%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##             main     #632      +/-   ##
==========================================
+ Coverage   96.05%   96.07%   +0.02%     
==========================================
  Files         112      112              
  Lines        4359     4357       -2     
==========================================
- Hits         4187     4186       -1     
+ Misses        172      171       -1     

Flag	Coverage Δ
unittests	96.07% <100.00%> (+0.02%)	⬆️

Flags with carried forward coverage won't be shown. Click here to find out more.

Impacted Files	Coverage Δ
doctr/models/predictor/pytorch.py	100.00% <ø> (ø)
doctr/models/predictor/tensorflow.py	100.00% <ø> (ø)
doctr/models/zoo.py	100.00% <100.00%> (ø)
doctr/models/recognition/crnn/pytorch.py	100.00% <0.00%> (ø)
doctr/datasets/utils.py	94.73% <0.00%> (+2.42%)	⬆️

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[fg-mindee]

Thanks for the PR! Good idea to document this on the high-level API, I added some doc suggestions

[fg-mindee]

Looks good, thanks!

[fg-mindee]

Thanks!