crash-digger continues to process unretraceable things

[Brian Murray]

From the retracer-i386 retracer log file:

12/14/16 20:32:09: retracing LP: #1539518 (left in pool: 0)
12/14/16 20:32:09: crash is release Ubuntu 10.04 which does not have a config available, skipping
12/14/16 20:47:02: Available releases: ['.bzr', 'Ubuntu 12.04', 'Ubuntu 14.04', 'Ubuntu 15.04', 'Ubuntu 16.04', 'Ubuntu 16.10', 'Ubuntu 17.04', 'crashdb.conf', 'crontab']
12/14/16 20:47:04: fill_pool: retrace pool now: set([1557377, 1528706, 1536075, 1565148, 1529291, 1529357, 1590542, 1553677, 1532499, 1551638, 1550170, 1555996, 1560998, 1528999, 1596316, 1538283, 1528049, 1531859, 1544116, 1539894, 1564409, 1537021, 1539518])

Notice that 1539518 is skipped and then is in the pool for the next run, it'd be better if the bug were modified so retracing isn't attempted again.

However, we must be wary that if crashes come from "Ubuntu 17.10" that the bug isn't modified as the release just may not yet exist in the config.