More robust git integration

[jeroen_van_splu]

1. No backups, undo, “trash can” or undo functionality for reports, dashboards and apps within workspaces. As a workaround, we have now implemented git sync for all workspaces, but this syncs only the reports. We would like to have backups and recovery possibilities for the full powerbi.com setup (workspace settings, apps, reports, dashboards etc.)
2. When you delete a semantic model, all reports and dashboards tiles, including in other workspaces, that reference the semantic model will be deleted. There is no way to opt-out of this. This is highly dangerous and should be opt-in only.
3. In our deployment pipeline, powerbi.com saw a double “Finance” semantic model. We are unsure why it thought a model with the same name was double. We were unable to indicate that there is no double model, but an update of an existing model. An easy solution would be to delete the double model, but this points us to our previous point: deleting a model takes down all reports linked to the model.
4. Small nuisance: in a deployment pipeline, parameters need to be set individually for each model, instead of setting them once for every environment. Powerbi.com also ignores the parameter dropdown values specified in the model.bim.