issue #869: added small documentation for executing scripts

Documentation/UserManual/Arangosh.md

@@ -59,6 +59,13 @@ For a list of available methods for the `db` object, type
     
     arangosh> db._help(); 
 
+Note that it also possible to execute scripts in arangosh and pass parameters 
+to the file, e.g.:
+
+	> arangosh --javascript.execute myscript.js parameter1 parameter2
+
+Inside the script you can use the "ARGUMENTS" array to access the parameters. 
+
 ArangoDB Shell Output {#UserManualArangoshOutput}
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