Lots of kernel installation failures with very long signatures:
 * https://errors.ubuntu.com/oops/024acb70-836a-11e2-9a69-e4115b0f8a4a
 * https://errors.ubuntu.com/oops/19c416f4-87ab-11e2-9621-2c768aafd08c

Discussed duplicate signatures:
 * https://bugs.launchpad.net/ubuntu/+source/dpkg/+bug/1096928

== Actions ==
 * Do not include the log as part of the identifier.
 * Bucket installation failures with "package:", followed by the package, package version (to be installed), and error message (ErrorMessage field).
 * Provide a specific bucket identifier for file name conflicts during package installation. Do not include the package version number in these.
 * Fix DKMS to not attach the whole build log as a signature. Pull out just the first line? (Bug Bug:1175785)
 * Filter all of these out of the phased updates "new buckets" query if they can produce a new signature without actually changing (package version changes, installation under another language).