Added scripts for Nexcloud and WebDAV

[jaller94]

Nextcloud is a powerful, open-source hub to synchronize files, contacts, calendars and much more across your devices and with other people.

The Nextcloud Conference 2022 took place this weekend in Berlin. Many people got together to learn about Nextcloud and develop new features. I took the time to create new apps on the Windmill Hub for Nextcloud and all the open protocols it supports.

Open standards added to the Windmill Hub

Files are exchanged using WebDAV. Calendars, tasks and journals are synced using CalDAV. Users can be managed using the Open Collaboration Services.

Biased resource types to start

Currently, the resource types of these scripts are nextcloud or at least oriented towards HTTP Basic Authentication, because that's what Nextcloud uses. Support for other authentication standards is something to be addressed when people request it or developers of other implementations join the Windmill community. For now, I think it's better to start with a single authentication method.