ACCUMULO-2950 Add an RpcWrapper class

  Adds an RpcWrapper class to reintroduce the previous behavior in Thrift 0.9.0
  that was broken by THRIFT-1805 in Thrift 0.9.1. This is done by extending the
  InvocationHandler that was already being used to incorporate Trace information
  into the RPC calls, but now also translates exceptions to one that Thrift
  0.9.1 will expose to the client as a TApplicationException.INTERNAL_ERROR