Fix UTF-8 output when using executable inventory files

The 'hostname' variable is then unicode, which breaks interpolating
stdout etc. contents into the output strings (they are bytes and cannot
be converted to Unicode using ASCII codec)

lib/ansible/callbacks.py

@@ -136,6 +136,9 @@ def command_generic_msg(hostname, result, oneline, caption):
     stderr = result.get('stderr', '')
     msg    = result.get('msg', '')
 
+    hostname = hostname.encode('utf-8')
+    caption  = caption.encode('utf-8')
+
     if not oneline:
         buf = "%s | %s | rc=%s >>\n" % (hostname, caption, result.get('rc',0))
         if stdout: