Fix copy detection corner case We were aborting if the copied from rev was before the cut-off limit, rather than the copied _to_ rev. The copied from rev can be arbitrarily old.

#!/bin/sh

hg init
echo This is file a1 > a
hg add a
hg commit -m "commit #0" -d "1000000 0"
touch b
hg add b
rm b
hg commit -A -m"comment #1" -d "1000000 0"