support API for official snappy framing about snappy HOT 5 CLOSED

I put a library for decoding the snappy stream format here:

go get github.com/glycerine/go-unsnap-stream

I've taken an initial pass at implementing Reader/Writers for the framing 
format at https://github.com/twotwotwo/sz/ but caveat emptor to the max: there 
is no test suite, this is immature code, etc. More detail is at 
https://code.google.com/p/snappy-go/issues/detail?id=4#c1

I should have updated this a while ago. At Bitly we have been using 
https://github.com/mreiferson/go-snappystream happily for a while.

With two days of hard work, I've implemented the framing for snappy: 
github.com/tgulacsi/sz

Then I've found this issue :)

At least the command-line client is usable (now using 
github.com/mreiferson/go-snappystream):
    go get github.com/tgulacsi/sz