Nextcloud 21 compatibility

[DD-githu]

It does not seem to work with Nextcloud 21, neither does https://github.com/apippin/files_excludedirs.
At least with occ files:scan on external storage the exclude is not respected. Any ideas?

[GuyPaddock]

Please give this unsigned release a spin; should work on 23x.:
https://github.com/Inveniem/nextcloud-files-excludedirs/releases/tag/v1.0.0-beta

I've also provided updated docs in the Readme (specifically, how it works with existing vs. newly-added files):
https://github.com/Inveniem/nextcloud-files-excludedirs/blob/master/README.md

The error about how it will "make your system unstable" is either because Composer deps weren't installed or the permissions are wrong on the plugin. I've tested this on my own 23.x deployment and it seems to work! If you use the release package I provided, the Composer deps are already included.

Feedback is welcome here:
https://github.com/Inveniem/nextcloud-files-excludedirs/issues

I'll have to look into publishing an official, signed package because I wasn't the original author of this one -- I just updated the work of others.