Please collect sources.list entries

apport-retrace can retrace crash reports in a sandbox, but it requires the user to supply a sources.list file for the distribution. Since the hosts that produce the crash report could have different sources lists (e.g. have different PPAs enabled or dynamic development repositories like in our case), providing one generic sources.list for all hosts is not suitable.

Thus please collect the sources.list (including the disabled entries) in the crash file to allow apport-retrace to use this information for building the sandbox.