Nextcloud V21 Update

### Nextcloud V21 Upgrade ###

## upgrade Nextcloud ##
sudo -u www-data php occ upgrade

sudo -u www-data php occ maintenance:mode --off

#1 Standart Telefonregion

## open nextcloud config.php
nano /var/www/nextcloud/config/config.php

add:
'default_phone_region' => 'DE',

#2 php-imagick fehlt die SVG-Unterstützung

## install libmagickcore-6.q16-6-extra ##

apt update
apt install libmagickcore-6.q16-6-extra