Performance improvement when working with large amounts of cells

[Fuzuki785]

This is:

• a bugfix
• a new feature
• refactoring
• additional unit tests

Checklist:

• Changes are covered by unit tests
  • Changes are covered by existing unit tests
  • New unit tests have been added
• Code style is respected
• Commit message explains why the change is made (see https://github.com/erlang/otp/wiki/Writing-good-commit-messages)
• CHANGELOG.md contains a short summary of the change and a link to the pull request if applicable
• Documentation is updated as necessary

Why this change is needed?

Related issue #4607

Improved the speed of the rangeToArrayYield method in Worksheet by:

• using a binary search algorithm first to approach the right index, before using linear search backwards and forwards to realign properly (limits the linear search iterations to about a row's worth of indices rather than the whole file's worth)
• improving the speed of the getCoordinates, getSortedCoordinates, getSortedCoordinatesInt method in Collections/Cells by adding a flag to avoid sorting the index array on every call and cache arrays to avoid using array_keys and array_values on every call to the methods

[oleibman]

@Fuzuki785 Thank you for the PR. It is difficult for me to evaluate its effectiveness. If I were to create a private repository with access allowed only to you and me, would you be willing to upload your file and code so that I can observe the performance improvements first-hand?

[Fuzuki785]

@oleibman I created a repository with a minimalist configuration for the issue, using sample data with only 95000 cells (instead of 1.8M cells): Fuzuki785/PhpSpreadsheet-4607-reprod.

I've copied the execution logs (time to read rows, file loading excluded) here from the README file for reference:

# Base version (5.0)
❯ php Reprod.php
Progress: 999
Time delta: 8.6829102039337 s
Progress: 1999
Time delta: 8.9077999591827 s
Progress: 2999
Time delta: 9.0496628284454 s
Progress: 3999
Time delta: 9.2766671180725 s
Progress: 4999
Time delta: 9.5125539302826 s
Total time: 45.43901014328 s

# Patched version
❯ php Reprod.php
Progress: 999
Time delta: 0.10127186775208 s
Progress: 1999
Time delta: 0.045258045196533 s
Progress: 2999
Time delta: 0.065037965774536 s
Progress: 3999
Time delta: 0.04623007774353 s
Progress: 4999
Time delta: 0.04681396484375 s
Total time: 0.30479502677917 s