Add a note in EasyRSA-Advanced.md

- The global options need to be set before the actual commands
- https://github.com/OpenVPN/easy-rsa/blob/master/easyrsa3/easyrsa#L219

doc/EasyRSA-Advanced.md

@@ -117,3 +117,5 @@ possible terse description is shown below:
     using any openssl password options like pass:1234 or env:var
  *  `EASYRSA_PASSOUT` (CLI: `--passout`) - allows to specify a source for password;
     using any openssl password options like pass:1234 or env:var
+    
+**NOTE:** the global options need to be provided before the actual commands.