webdav as external storage

**Is your feature request related to a problem? Please describe.**
local storage is unsafe and not easy/intuitive to use, and a cloud solution cost money. in my experience there is nothing in between. i would like to just buy a nas and host my data that way without too muche hassel.

**Describe the solution you'd like**
I would like support for webdav as cloud storage.

**Describe alternatives you've considered**
a nas with a reddis. but i think webdav is more widely avalible.