[Feat] Add layout scripts and update augmentations to Sample strategy

[felixdittrich92]

This PR:

• Add latency, eval and train scripts for layout analysis
• Add first documentation updates
• Minor fixes for the dataset and dataloading
• Refactor augmentation to Sample strategy and update tests

[codecov]

Codecov Report

❌ Patch coverage is 92.85714% with 21 lines in your changes missing coverage. Please review.
✅ Project coverage is 96.67%. Comparing base (bc0db21) to head (cd8cae1).

Files with missing lines	Patch %	Lines
doctr/models/layout/lw_detr/base.py	85.29%	10 Missing ⚠️
doctr/transforms/modules/base.py	90.90%	6 Missing ⚠️
doctr/transforms/modules/pytorch.py	90.90%	5 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #2067      +/-   ##
==========================================
- Coverage   96.70%   96.67%   -0.03%     
==========================================
  Files         156      156              
  Lines        7276     7403     +127     
==========================================
+ Hits         7036     7157     +121     
- Misses        240      246       +6     

Flag	Coverage Δ
unittests	96.67% <92.85%> (-0.03%)	⬇️

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