Improve PowerShell and REST API to work with standalone Datasets

Scenario:
1. Create a new report in PBI Desktop, publish it to the workspace. It creates a dataset and a report.
2. Remove the report from the workspace. The dataset remains as-is and can still be used as a data source for other reports.
3. Try downloading the .PBIX file of the dataset. You can do it manually from the workspace in the browser. But you can't do this using PowerShell or REST API. PowerShell command Export-PowerBI doesn't work if there is no report bound to the dataset, same with REST API.

Please improve PowerShell and REST API to support working with standalone datasets.