Verify WebDAV during Setup

[danimo]

Verify that WebDAV works properly and show an error if it doesn't

• Web server must not use its own WebDAV engine
• Web server must permit WebDAV verbs (PROPFIND et al)

The right place would be a self-test during setup.

This is important for the user expirience for people using WebDAV mounts and the client, since IIS and paranoid apache setups will cause trouble (IIS explicitly disallows some HTTP verbs by default, regardless of the internal WebDAV support).

[DeepDiver1975]

WebDAV will only be accessible after successful installation.

I'll try to get some kind of post-setup test going because is no candidate for a check on every request.