feat: iterator over rust range

[dimastbk]

• #42

Memory usage:

• red - openpyxl, read_only=True, iter_rows()
• black - master, to_python()
• blue - this PR, iter_rows()

example file (saved as xlsx in LibreOffice).

TODO:

1. Fix empty cells and tests

[spumer]

Any updates?

[alanxoc3]

Thanks for putting together the PoC. This would be really cool to see available in the official package.

So.... I'm bumping this. Any updates?