correct sections

docs/actors.md

@@ -224,7 +224,7 @@ use('json')            // core json module
 use('otherlib/foo')    // dependency 'otherlib', file foo.cm
 ```
 
-Files starting with underscore (`_helper.cm`) are private to the package.
+Files in the `internal/` directory are private to the package.
 
 ## Example: Simple Actor System