Configuration of auto data back-up in UI and restore from backup option in install steps

Tags: #<Tag:0x00007f739082a5e0>

To help restore HA after a SD card/memory/system failure, or even an update gone wrong.

1 - allow configuration of backup to dropbox (or similar) via UI. (perhaps as an Addon)
2 - allow this to be configured as part of install (cause lets be honest no one realises they need this until it’s too late).
3 - allow restore from backup option in install.