net = convertoldnet(net)
net = convertoldnet(net) takes a network net and, if appropriate,
converts it from pre-2.3 to the current format. The difference is simply
that in MLPs and the MLP sub-net of MDNs the field actfn has been
renamed outfn to make it consistent with GLM and RBF networks.
If the network is not old-format or an MLP or MDN it is left unchanged.
mlp, mdnCopyright (c) Ian T Nabney (1996-9)