make appendfile simpler so it does not break with revlogng on windows.
it used to cache open files. this made revlogng break because it wants
to rename files when splitting .i into .i/.d, but cannot rename or unlink
open files on windows.
new code is bit slower, but safe on linux and windows. proper fix for
too many open/close of changelog/manifest belongs in different place.
can get 10% speed improvement back.
#!/bin/sh
hg init 1
echo '[ui]' >> 1/.hg/hgrc
echo 'timeout = 10' >> 1/.hg/hgrc
echo foo > 1/foo
hg --cwd 1 ci -A -m foo
hg clone 1 2
hg clone 2 3
echo '[hooks]' >> 2/.hg/hgrc
echo 'changegroup.push = hg push -qf ../1' >> 2/.hg/hgrc
echo bar >> 3/foo
hg --cwd 3 ci -m bar
hg --cwd 3 push ../2