p-s: gracefully handle missing/disappearing sections

do not abort the slave, just skip the section

Signed-off-by: Andreas Beckmann <anbe@debian.org>
dwke: gracefully handle missing sections

Signed-off-by: Andreas Beckmann <anbe@debian.org>
p-r: gracefully handle missing sections

Signed-off-by: Andreas Beckmann <anbe@debian.org>
dwke: open PTS link in new window

Signed-off-by: Andreas Beckmann <anbe@debian.org>
dwke: sync config defaults with piuparts-report

need upgrade-test-distros, too, as that is an alternative source for distro

Signed-off-by: Andreas Beckmann <anbe@debian.org>
dwke: ignore disappearing logfiles

mtime() may fail if the file no longer exists

Signed-off-by: Andreas Beckmann <anbe@debian.org>