### Summary
Address
[#1136](https://github.com/Unstructured-IO/unstructured/issues/1136) for
`hi_res` and `fast` strategies. The `ocr_only` strategy does not include
coordinates.
- add functionality to switch sort mode between the current `basic`
sorting and the new `xy-cut` sorting for `hi_res` and `fast` strategies
- add the script to evaluate the `xy-cut` sorting approach
- add jupyter notebook to provide evaluation and visualization for the
`xy-cut` sorting approach
### Evaluation
```
export PYTHONPATH=.:$PYTHONPATH && python examples/custom-layout-order/evaluate_xy_cut_sorting.py <file_path> <strategy>
```
Here, the file should be under the project root directory. For example,
```
export PYTHONPATH=.:$PYTHONPATH && python examples/custom-layout-order/evaluate_xy_cut_sorting.py example-docs/multi-column-2p.pdf fast
```
Summary
* Updates "fast" PDF output element ordering to be consistent across Python versions by using the X,Y coordinates of elements extracted
* Added PDFs ingest tests with fast strategy with new script ./test_unstructured_ingest/test-ingest-pdf-fast-reprocess.sh
Updated ingest tests procedure:
* Processing files with hi_res strategy, and preserve downloads to repo files-ingest-download/<ingest_test_name>
* Reprocessing all PDFs with fast strategy from local file files-ingest-download, the partition outputs are stored at expected-structured-output/pdf-fast-reprocess/<ingest_test_name>
Test
* Reproduce tests with ./scripts/ingest-test-fixtures-update.sh , should expect no update. Also don't need any secret tokens since relevant tests won't produce PDFs.