Enable demandimport only in scripts, not in importable modules (issue605) This way other applications can choose if and when they want this feature, because it might be problematic if those applications rely on ImportError.

#!/bin/sh

hg
hg -q
hg help
hg -q help
hg add -h
hg add --skjdfks
hg help diff
hg help status
hg -q help status
hg help foo
hg skjdfks

exit 0