Reduce string duplication in compression code This cuts down on string copies and allows buffers (instead of strings) to be passed into the compression code

#!/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