twitter/twemproxy — pull request #254 by idning (2014-08-28 12:52:19+00:00)
Title: xscan supported

hscan/sscan/zscan implement.

there is a trick on handler hscan/sscan/zscan response, which has nested multi-bulk

these command replay a nested multi-bulk with a number and a multi bulk like this:

- mulit-bulk
- cursor
- mulit-bulk
- val1
- val2
- val3

in this case, there is only one sub-multi-bulk,
and it's the last element of parent, we can handle it like tail-recursive.