#42 Script late binding

[Paolo Marrone]

Now the scripts to be executed by a neural network are
contained into the NN and transported and executed
along with it.
It would be nice to have a sort of 'late binding' for a
script, i.e. the possibility to indicate an external
file containing the script's code. In this manner the
final user can decide at the run time the code that
must be executed.