convert: Use clone's behaviour for the default destionation name. Adjusted the documentation for this and for the fact that the destionation is created even if a name is specified.

#!/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"