Add rename/mv command. This is the logical equivalent of copy and remove, and is in fact implemented as such. It doesn't use the remove command directly.

#!/bin/sh

hg init a
cd a
echo a > foo
hg add foo
hg commit -m 1 -d "0 0"
rm foo
hg remove foo
hg commit -m 2 -d "0 0"

cd ..
hg clone a b