add support for streaming clone. existing clone code uses pull to get changes from remote repo. is very slow, uses lots of memory and cpu. new clone code has server write file data straight to client, client writes file data straight to disk. memory and cpu used are very low, clone is much faster over lan. new client can still clone with pull, can still clone from older servers. new server can still serve older clients.

changeset:   0:0acdaf898367
tag:         tip
user:        test
date:        Mon Jan 12 13:46:40 1970 +0000
summary:     test

b789fdd96dc2f3bd229c1dd8eedf0fc60e2b68e3 644 a
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1 files, 1 changesets, 1 total revisions