You scream, I scream, We all scream for exceptions

You scream, I scream, We all scream for exceptions

    Added exception defintions and specifiers to thrift grammar

    Modified C++ code generator to to catch and serialize exceptions on the server side and unmarshall and throw them on the client side.

Modified grammar to require ","  after each service function declaration to keep it consistent with struct declaration syntax

    This checkin officially breaks the old parser

git-svn-id: https://svn.apache.org/repos/asf/incubator/thrift/trunk@664754 13f79535-47bb-0310-9956-ffa450edef68