DataTables/DataTables — pull request #330 by chrisgeo (2014-05-21 01:26:11+00:00)
Title: * Allow the error state in the JSON returned to determine the use of the error callback if it exists.

Instead of logging and using _fnLog with a level state of "0" everywhere (throwing alerts everywhere) and also to allow the use of custom error callbacks with XMLHTTPRequests, use the error callback defined.

**NOTE**: This is mostly a temporary fix for the author to decide the best path to implement this as a globally available function.