Add TSV, ODS & XLSX to export options

[LenaWil]

TSV with BOM works fine, but Excel doesn’t open them by default. ODS doesn’t work properly if both unicode and Excel are used. XLSX of course does work correctly, but I don’t want to use a microsoft specific format.

Fixes #301.

I should still write tests, but I would like others to review it first.

[LenaWil]

Maybe I should also include a BOM in the .csv exports… what are y’alls thought on it?

[codecov[bot]]

Codecov Report

Patch coverage: 90.90% and no project coverage change

Comparison is base (9d83be4) 95.77% compared to head (44abd0c) 95.77%.

Additional details and impacted files

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[LenaWil]

Okay, how extensive should the tests be?

[DutcherNL]

Okay, how extensive should the tests be?

Depends on how important/ how easy it is to accidentally break it. In your case I would only add a test that ensures export_data indeed adds the 'zero width no break space' to the beginning of the file.