Parse logs and categorize types of (temporary) failures

It would be useful to be able to categorize failures (both fail and tmpfail statuses), so that we can group these failures when investigating them. This could use some AI technique such as Bayesian classification or what not, or even a set of regular expressions as in collab-qa-tools. There are two challenges here:

1. how to do this classification
2. how to integrate this with the UI in order to enable us to investigate the issues.