feat: Added rbox_iou function with a memory-savy option

[fg-mindee]

This PR introduces the following modifications:

• adds rbox_iou function to compute IoU between sets of rotated bounding boxes
• replace iou computation in task metrics with rbox_iou while adding a use_broadcasting boolean flag
• adds missing constructor arg description in docstrings
• fixes typos in multiple docstrings

Any feedback is welcome!

[codecov]

Codecov Report

Merging #659 (5c979f6) into main (1937843) will increase coverage by 0.04%.
The diff coverage is 89.74%.

@@            Coverage Diff             @@
##             main     #659      +/-   ##
==========================================
+ Coverage   96.07%   96.12%   +0.04%     
==========================================
  Files         113      113              
  Lines        4386     4410      +24     
==========================================
+ Hits         4214     4239      +25     
+ Misses        172      171       -1     

Flag	Coverage Δ
unittests	96.12% <89.74%> (+0.04%)	⬆️

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Impacted Files	Coverage Δ
doctr/utils/metrics.py	97.40% <89.74%> (+1.26%)	⬆️
...dels/detection/differentiable_binarization/base.py	91.30% <0.00%> (-0.63%)	⬇️

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[charlesmindee]

Thanks!