add documentation

README.md

@@ -36,7 +36,18 @@ Usage
 -----
 
 ```
-$ sudo ./bin/vhost-add
+USAGE:
+  ./bin/vhost-add [options]
+
+OPTIONS:
+  -d                 The domain name
+  -a                 Aliase(s)
+  -m value           Enable *http* or *https*
+  -r                 Force redirection of http to https
+  -p value           Enable PHP with the given version (eg: 8.0)
+  -u value           Username in the system
+  -i                 Enable script interactivity
+  -h                 Show this help
 ```
 
 ![](https://www.deblan.io/~simon/vhost-manager/vhost-manager2.gif)