ffnet-0.7 released

This release contains couple of important changes:
- neural network can be trained now using the power of multi-processor
systems (see example mptrain.py)
- attributes which are necessary for calculation of network derivatives
are now generated only on demand;
- data normalization limits are not changed when retrainig with new
data set; net.renormalize = True have to be set first;
- compatibility with newest versions of numpy, scipy and networkx
is enhanced;
- support for *export to java* and *drawing network with drawffnet*
is dropped.
However basic API is almost untouched. Exactly the same trainig scripts
as for older versions should work without problems.

BTW: ffnet-0.7 Windows packagers wanted...