fix examples in cmd/venti

I am not entirely sure if this is the right fix, but the examples in cmd/venti return the error:

"read count too large for protocol"

This is because of the following check in vtreadpacket (libventi/client.c) which was added to support blocks > 64k:
	if(z->version[1] == '2' && n >= (1<<16)) {
		werrstr("read count too large for protocol");
		return nil;
	}

Setting VtMaxLumpSize to (1<<16)-1 fixes the issue.

[rsc, 2012-05-02 01:28:29]

Thanks for this patch.  Can you let me know your name for listing in
the CONTRIBUTORS file?

[adkulkar_indiana.edu, 2012-05-04 04:33:23]

On Tue, May 1, 2012 at 7:28 PM, Russ Cox <rsc@golang.org> wrote:

> Thanks for this patch.  Can you let me know your name for listing in
> the CONTRIBUTORS file?
>

Sure. It's:

Abhishek Kulkarni <adkulkar@umail.iu.edu>

Thanks!

[rsc, 2012-05-29 17:34:58]

*** Submitted as http://code.google.com/p/plan9port/source/detail?r=1eb94efa54c9
***

venti: fix VtMaxLumpSize

R=rsc, adkulkar
CC=plan9port.codebot
http://codereview.appspot.com/6108047

Committer: Russ Cox <rsc@swtch.com>