Install instructions in one place

[michielbdejong]

I know we created install instructions for the test server we created in August but I don't know where I put those.
Also, the development install refers to https://github.com/pdsinterop/test-suites, I'm going to test whether that is still current

[michielbdejong]

The manual install still mentions editing the .htaccess file, I think that's also no longer necessary

[michielbdejong]

Ah, and there is https://github.com/pdsinterop/solid-nextcloud/blob/main/INSTALL.md

[michielbdejong]

Did some cleanup in the revisit-install-instruction branch.
Now creating generic Nextcloud setup instructions in a gist, which we can refer to from these instructions and also from other Nextcloud-based projects when we want to (I have a need for it from peppol-nextcloud and sciencemesh-nextcloud as well).

[michielbdejong]

I'm trying out how to install our app on top of the ubuntu-snap-nextcloud instructions from DigitalOcean now