Change the front end route for folders to /dashboards/f/<uid>/<slug of folder title>.
Use new route for deleting dashboard/folder by uid.
Retrieve dashboard/folder by uid when moving or deleting dashboards/folders.
* dashfolders: fix url for create dashboard from manage dashboards
Don't include folderId querystring if you don't manage a folder and
creating a new dashboard from there.
* dashfolders: don't store folderId in dashboard model
Use folderId from meta instead
#10307
* dashfolders: minor ux fix
* dashfolders: minor fix for edit folder title
bulk delete dashboards synchronously
moved bulk delete and move dashboards to backend_srv
better error handling/messages when moving and deleting folders/dashboards
fixes#10181
