Add exemptions for incompatible UAs

[LukasReschke]

Some user agents are notorious and don't really properly follow HTTP
specifications. For those, have an automated opt-out. Since the protection
for remote.php is applied in base.php as starting point we need to opt out
here.

Fixes #223
Fixes #1237

In combination with #797

[mention-bot]

@LukasReschke, thanks for your PR! By analyzing the annotation information on this pull request, we identified @DeepDiver1975, @bartv2 and @icewind1991 to be potential reviewers

[icewind1991]

👍 looks good

[MorrisJobke]

Tested and works 👍

[MorrisJobke]

@LukasReschke @karlitschek Backport to stable10?

[ochurlaud]

Just tested, it still does not work in my case with the last DAVdroid (1.3-ose) and KOrganizer.

The only problem is about the calendar and contacts synchronization. Mail sent to Lukas for more tests.

[LukasReschke]

@LukasReschke @karlitschek Backport to stable10?

Should do that. Will create a PR containing both issues.

[LukasReschke]

=> #1331

[karlitschek]

please backport 👍

[Chluz]

Hi, Coming from the KeeWeb issues thread keeweb/keeweb#492 , adding the following exception for incompatible user agents fixed the KeeWeb 1.3.3 webdav client using nextcloud 11.0.1:

             $incompatibleUserAgents = [
                        // OS X Finder
                        '/^WebDAVFS/',
                        // KeeWeb client
                        '/KeeWeb\/\d[.]\d[.]\d/',
                ];

Is this something worth making a fork/merge request for ?

[huguesgr]

Can anyone reply to @Chluz?
After each Nextcloud upgrade, I have to add the KeeWeb regex, otherwise it breaks KeeWeb synchronisations.

[acidsploit]

Yes, please fix this.

@Chluz @Wohlraj I'm having the same issue.