Use unsigned version format.
This way can use one additional bit, and when encountering invalid revlogs
with the first bit set don't produce python warnings or strange error messages.
--- a/mercurial/revlog.py Fri Dec 01 23:16:12 2006 +0100
+++ b/mercurial/revlog.py Fri Dec 01 23:27:53 2006 +0100
@@ -81,7 +81,7 @@
# 32 bytes: nodeid
indexformatng = ">Qiiiiii20s12x"
ngshaoffset = 32
-versionformat = ">i"
+versionformat = ">I"
class lazyparser(object):
"""