fix the implementation of GenericValue(std::bsaic_string&,...) and get rid of warning
add rapidjson::{GenericWriteStream,GenericReadStream} and ajust the rest code to use nonecopyable streams.

The changes are based on https://code.google.com/p/rapidjson/issues/detail?id=20
Merge pull request #2 from doo/feature-reader-writer-std-streams

Feature reader writer std streams