Custom env bug affecting lh_setupapt

[hendry at iki.fi (Kai Hendry)]

I noticed that LIVE_REPOSITORIES and LIVE_REPOSITORY_* aren't exported
properly for lh_setupapt.

I'm not too sure the best way to fix it. Perhaps just source
$LIVE_CONFIG from lh_setupapt?

I think there is bug in the Configuration routine in main.sh. If
LIVE_CONFIG is unset, LIVE_CONFIG=${CONFIG}.

I also noticed lh_setupapt needs some work to support my repo.

Best wishes,