bytes.Buffer: add Seek, WriteAt, ReadAt, Close, and Closed

bytes.Buffer: add Seek, WriteAt, ReadAt, Close, and Closed
Fixes issue 440.

Background: makes bytes.Buffer API more consistent with os.File
https://groups.google.com/group/golang-nuts/browse_thread/thread/1eaded9352517dbd

[rsc1, 2010-08-26 15:16:41]

Saw this in the list.  Maybe you're not ready for review
but I want to comment on where this is heading.
It looks like you copied someone else's code, and we
objected to that very same code the first time.
http://codereview.appspot.com/179074

(If you're not ready for comments, please don't set the
Reviewer: or CC: fields when creating the change, and
then we won't see it.)

[bytbox, 2010-08-26 15:27:07]

On 8/26/10, rsc@google.com <rsc@google.com> wrote:
> Saw this in the list.  Maybe you're not ready for review
> but I want to comment on where this is heading.
> It looks like you copied someone else's code, and we
> objected to that very same code the first time.
> http://codereview.appspot.com/179074
I did not see that - I was lifting code from the patch provided on the
issue tracker. Thanks for the pointer. (It looks like most of the
objectionable parts have already been left out, and the only remaining
problem is: does this belong in bytes.Buffer at all?)

> (If you're not ready for comments, please don't set the
> Reviewer: or CC: fields when creating the change, and
> then we won't see it.)
Ok.


-- 
Scott Lawrence

[rsc, 2010-08-26 15:30:19]

> I did not see that - I was lifting code from the patch provided on the
> issue tracker. Thanks for the pointer. (It looks like most of the
> objectionable parts have already been left out, and the only remaining
> problem is: does this belong in bytes.Buffer at all?)

It does not.  See the comment about Seek.

[rsc1, 2010-08-30 19:45:53]

removing reviewers

[bytbox, 2010-08-31 22:17:05]

This is a test. If by some great chance it goes through, rather than 500'ing,
please ignore it.