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
python -c 'print "confuse str.splitlines\nembedded\rnewline"' > a
hg ci -Ama -d '1 0'
echo clean diff >> a
hg ci -mb -d '2 0'
hg diff -r0 -r1