Fix invalid shebang

As @TomyLobo pointed out the shebang in the README is not correct. Fix
the description.

Author: n0la

README.md

@@ -64,17 +64,27 @@ EOS
 ```
 
 In this mode lines starting with ```#``` are ignored. This allows rcon to be
-used as a script interpreter:
-
-```
-#!/usr/bin/rcon -H somehost -p someport -P somepass
+used as a script interpreter. Just pass it the script file through stdin:
 
+```shell
+$ cat somescript.txt
+# This is a comment
 status
+
+# and this too!
 sm plugins list
 
 cvarlist
 ```
 
+And execute your script like this:
+
+```shell
+$ rcon -H somehost -p someport -P somepass < somescript.txt
+# Or:
+$ cat somescript.txt | rcon -H somehost -p someport -P somepass
+```
+
 ## Exit Code
 
 The command exit with 0 on success, and some arbitrary non-zero exit code on