Resolve #1298

* use serial.load in CIFAR10._unpickle
* remove "scripts/tutorials/grbm_smd/make_dataset.py" from pep8 whitelist
* refine serial.load for interoparability between Python 2 and 3
* remove N and np, aliases of numpy
Shouldn't we just add conditional logic in `serial.load` to add the encoding? Perhaps even add it as an overrideable keyword argument to `serial.load`.