Honour client's request for binary data transfer.
Honour client's request for binary data transfer.

When coordinator gets data from the datanode, it always gets it in TEXT mode.
But if the client has requested binary transfer of the data, then it must not
forward the data received from the datanode as it is. Rather it must send each
column in the desired format.

While this should fix the JDBC or libpq issue with binary data transfer, we
should really see if the coordinator to datanode communication can also use
binary mode for performance reason. But thats a separate patch.

zeroae/postgres-xl,zeroae/postgres-xl,zeroae/postgres-xl,zeroae/postgres-xl,zeroae/postgres-xl