Merge branch '34-update-readme' into 'master'

Resolve "Update readme"

Closes #34

See merge request !10

README.md

 # ISPConfig 3 AutoInstaller
-
+![alt text](https://www.ispconfig.org/wp-content/themes/ispconfig/images/ispconfig_logo.png "") \
 [![pipeline status](https://git.ispconfig.org/ispconfig/ispconfig-autoinstaller/badges/master/pipeline.svg)](https://git.ispconfig.org/ispconfig/ispconfig-autoinstaller/commits/master)   
 
-This script configures your server (Ubuntu 18.04 / Debian 9 and 10 currently) following the "perfect server tutorials" from howtoforge.com and installs ISPConfig 3.
+This script configures your server (Ubuntu 18.04, Ubuntu 20.04, Debian 9 and 10 currently) following the "perfect server tutorials" from howtoforge.com and installs ISPConfig 3.
 
 ## Using the script
-You can use the script with curl
+You can use the script with curl  
 `curl https://get.ispconfig.org | sh`  
 or with wget  
 `wget -O - https://get.ispconfig.org | sh`
@@ -27,4 +27,7 @@ or using wget
 If you checked out the installer from git you can simply pass the arguments to the script itself:  
 `./ispc3-ai.sh --debug --no-mailman`
 
-To see all available arguments, please provide the `--help` argument.
\ No newline at end of file
+To see all available arguments, please provide the `--help` argument:  
+`curl https://get.ispconfig.org | sh -s -- --help`  
+or using wget  
+`wget -O - https://get.ispconfig.org | sh -s -- --help`