Update project structure, add pipeline and tests

# Conflicts:
#	configs/config.yaml

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# Committer: Hayk Arutyunyan <haykarutyunyan@MacBook-Pro-Hayk.local>
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# interactive rebase in progress; onto 3d54e9d
# Last command done (1 command done):
#    pick e710af8 # Update project structure, add pipeline and tests
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# You are currently rebasing branch 'main' on '3d54e9d'.
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# Changes to be committed:
#	modified:   configs/config.yaml
#	deleted:    notebooks/mnemo_ocr_final_v03_color_v01.ipynb
#	new file:   pytest.ini
#	new file:   src/__init__.py
#	new file:   src/config_loader.py
#	new file:   src/ocr_utils.py
#	new file:   src/pipeline.py
#	new file:   tests/__init__.py
#	new file:   tests/conftest.py
#	new file:   tests/test_extract_text.py
#	new file:   tests/test_iter_input_images.py
#	new file:   tests/test_ocr_utils.py
#	new file:   tests/test_process_all_images.py
#