[MERGE] Cherrypick and polish the RemoteSink for streaming push.

[Robert Collins]

This is a cleaned up version of the streaming push Andrew and I put
together; it uses the NetworkRecordStream infrastructure to send deltas
or fulltexts in a single stream to a smart server. This stream can't
handle stacked repositories yet, but it will in the near future once we
integrate in the [approved] suspend/resume of write groups to this smart
verb.

As we're at the start of a release I think we can put this in and update
the verb a commit or two later, but if needed we can batch this up with
the needed changes.

-Rob
-------------- next part --------------
A non-text attachment was scrubbed...
Name: fetch-RemoteSink-4028.patch
Type: text/x-patch
Size: 35829 bytes
Desc: not available
Url : https://lists.ubuntu.com/archives/bazaar/attachments/20090220/d310bde9/attachment-0001.bin 
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: application/pgp-signature
Size: 197 bytes
Desc: This is a digitally signed message part
Url : https://lists.ubuntu.com/archives/bazaar/attachments/20090220/d310bde9/attachment-0001.pgp