Add support for private data in callback functions.

Add support for private data in callback functions.

Used this in test program to allow deserialising a fast transfer stream
into a mapistore context. You can use it something like:
./bin/check_fasttransfer --showprogress --mapistore=/tmp/fx_fsocpf --profile=e2k10
(note that the directory should exist and be empty).

Fixed a couple of issues with the parser - missing property handling.

Updated mapitest to suit API changes.