Apt apport integration improvements

Apt and update-manager report package installation failure automatically now. This is a good thing, but it also leads to a lot of report and to a lot of incorrect reports. Failures in e.g. gedit postinst may be caued by e.g. gconf failing in this postinst and are therefore not a gedit problem (per se). We should discuss what we can do to improve the quality in the reports (run everything with sh -x ;)