Describe the bug

Cacti generates an XML error when there is no 'direction' XML field specified for a Data Query field. This was noted in the following forum post: http://forums.cacti.net/viewtopic.php?p=293505#p293505

To Reproduce

Steps to reproduce the behavior:

1. Create an Data Query XML file

2. Include many fields, one that does not have a 'direction' attribute

3. Run the Data Query

4. See error

Expected behavior

Cacti should be able to handle this circumstance without warnings.