Calamine 0.9.0 now supports OpenDocument SpreadSheets


calamine is now an Excel and OpenDocument Speadsheets (*.ods) parser.

In order to keep the API consistent, I had to rename the Excel struct into a more general Sheets struct, which is a breaking change.

The implementation itself covers all basic data-types like existing Excel readers do. It doesn’t cover scripts parsing yet as I’m not sure about the internal organization.