make revlog.addgroup pass its file handles to addrevision
This should fix issue255.
It looks like the problem there happens when addgroup calls addrevision
to add a full revision, and addrevision decides to split the index file
into a .i/.d pair. Since addgroup has an open file handle for the
index file, the renaming of the new .i file to its final name fails on
windows.
#!/bin/sh
hg init
mkfifo p
hg serve --stdio < p &
P=$!
(echo lock; echo addchangegroup; sleep 5) > p &
Q=$!
sleep 3
kill -HUP $P
wait
ls .hg