Add the plugin allowing to migrate from Google to Nextcloud
Summary
Looks like it's possible to migrate data from Google, Dropbox, OneDrive and ownCloud to Nextcloud.
It would make things easier if the tool could be implemented alongside a good howto, in order to make it possible for everyone to easily transfer data from their Google account to their /e/ account.
Description
Who will use the new feature?
People who wants to leave Google, people who are struggling adding their Google account on /e/OS.
What is the target of the new feature for this user?
Leave Google more easily.
Why this user would like to use this feature?
To leave Google.
Examples
Reflection
Mockups
Diagrams