If an exception is thrown while writing data, instead of letting the developer handle this situation gracefully, Spout can attempt to delete all the temporary files that were created so far, as well as the output file as it won't be completed and therefore corrupted.
The ZipHelper interface is now more generic and allow single files to be added.
It supports adding uncompressed files (for PHP7+), which is required to have the mime detection magic work with ODS files.
Also fixed a few issues with the created ODS file (thanks to https://odf-validator.rhcloud.com/)
Spout can now read ODS files.
It's on par with the XLSX reader. The only difference is that the row iterator cannot be rewound.
It supports the different output formats from LibreOffice and Excel, skipping extra rows/cells if needed.
Remove num-columns-repeated and num-rows-repeated as it does not seem to be required (LibreOffice does not add them).
This greatly simplifies the writer and the XML output.
Added some optional attributes to help LibreOffice with cell values caching ("calcext")
Added ODS writer
Refactored XLSX writer to abstract some pieces into an abstract multi-sheets writer
Created an abstract style helper
Moved shared components around
