wrong jason format of index docs in ch3.

curl -XPOST http://localhost:9200/index/fulltext/1 -d'
{"content":"美国留给伊拉克的是个烂摊子吗"}
'
======================================
like above.elder seems ok,but can not be searched.
Merge pull request #38 from wsk528/patch-1

wrong jason format of index docs in ch3.