Merge branch '6012-update-readme-md' into 'develop'

Resolve "Update README.md"

Closes #6012

See merge request ispconfig/ispconfig3!1388

Author: Marius Burkard

README.md

@@ -1,13 +1,43 @@
 # ISPConfig - Hosting Control Panel
-
+![alt text](https://www.ispconfig.org/wp-content/themes/ispconfig/images/ispconfig_logo.png "") \
 Development branch: [![pipeline status](https://git.ispconfig.org/ispconfig/ispconfig3/badges/develop/pipeline.svg)](https://git.ispconfig.org/ispconfig/ispconfig3/commits/develop)
 
-
+## Functions
 - Manage multiple servers from one control panel
-- Web server management (Apache2 and nginx)
-- Mail server management (with virtual mail users)
-- DNS server management (BIND and MyDNS)
+- Single server, multiserver and mirrored clusters.
+- Webserver management (Apache2 and nginx)
+- Mailserver management
+- DNS server management (BIND and PowerDNS)
 - Virtualization (OpenVZ)
-- Administrator, reseller and client login
-- Configuration mirroring and clusters
+- Administrator, reseller, client and mailuser login
 - Open Source software (BSD license)
+
+## Supported daemons
+- HTTP: Apache2 and nginx
+- HTTP stats: Webalizer, GoAccess and AWStats
+- Let's Encrypt: Acme.sh and certbot
+- SMTP: Postfix
+- POP3/IMAP: Dovecot
+- Spamfilter: Rspamd and Amavis
+- FTP: PureFTPD
+- DNS: BIND9 and PowerDNS
+- Database: MariaDB and MySQL
+
+## Supported operating systems
+- Debian 9, 10, and testing
+- Ubuntu 16.04 - 20.04
+- CentOS 7 and 8
+
+## Auto-install script
+You can install ISPConfig with our official autoinstaller: https://git.ispconfig.org/ispconfig/ispconfig-autoinstaller/-/blob/master/README.md
+
+## Migration tool
+The Migration Tool helps you to import data from other control panels (currently ISPConfig 2 and 3 – 3.2, Plesk 10 – 12.5, Plesk Onyx, CPanel** and Confixx 3). For more information, see https://www.ispconfig.org/add-ons/ispconfig-migration-tool/
+
+** The Migration Toolkit contains now beta support for migrating CPanel to ISPConfig.
+
+## Documentation
+You can support ISPConfig development by buying the manual: https://www.ispconfig.org/documentation/
+
+## Contributing
+If you like to contribute to the ISPConfig development, please send an email to: dev [at] ispconfig [dot] org.