error report is not included in --logfile nor is it available for download as a csv

[aztlan2k]

When i run into errors while in distributed mode, i can examine them in the UI (under Failures) and they also get output to stderr when I kill the master... but there needs to be a way to save this information.

Either or both of these would be great:

1. Provide another link to download the error report as a CSV, much like the requests and distribution report.
2. Log the error report to the --logfile on quitting, not just to stderr.

[heyman]

I added the ability to download the data in CSV format.

There's actually an undocumented way of grabbing the data in the currently released version as well. By accessing the /exceptions endpoint, you can get the data in JSON format.