rb: BufferedTransport should flush on close [THRIFT-49]

This also adds code and spec so nothing will be written to the transport
if there's nothing in the write buffer.


git-svn-id: https://svn.apache.org/repos/asf/incubator/thrift/trunk@671967 13f79535-47bb-0310-9956-ffa450edef68
2 files changed