Add the ability to convert existing SSAS Pivot Charts from Excel spreadsheets to PowerBI

[nicolas_mettais]

For organisatons with SSAS, many users already have Excel spreadsheets where the built Pivot tables and charts to query their SSAS cube. Now this cube is available to PowerBI thanks to the Gateway and SSAS connector. It would be great to be able to simply convert these existing Excel files into PowerBI reports and dashboards, in order to avoid a long efort of rebuilding all the reports from scratch.