In fd9eb16b24, the option
"services.nextcloud.nginx.enable" has been removed since the module now
exclusively supports nginx only.
Unfortunately, with the option gone from the manual, the link in the
Nextcloud-specific documentation referencing the NixOS option also
became a dead link and thus the manual will no longer build.
I also removed a second reference to this option in the Nextcloud-
specific documentation, which while it doesn't lead to a build error in
the manual is nevertheless a good idea to remove as well to ensure we
don't present outdated information to readers of the manual.
Signed-off-by: aszlig <aszlig@nix.build>
Cc: @DavHau, @Ma27