Meaningless tweaks
Linux file path support and a little less memory required
Fix mistake with endianness
Some error checking
Restructure and add capability of saving and restoring a net from a list

The list can then be saved to file by converting it to and from a string.
The restructuring was squishing aimath.py and neurons.py into feedforward.py which makes
imports a little easier to deal with.
There were also some tweaks to tasks.
Add test_pynet.py