Warnings as errors, builds clean. Had to do some horrible hacks:
1) Include custom implementation of a lib function just so we could
link against stuff built with older VS.
2) Include legacy symbols for old io for the same reason.
This commit includes code that was missing from the original Python PR which adds support for the multiprocessing module in Python. I have no idea why this was missed, but it was. The code also includes adjustments to the loader which attempts to resolve modules appropriately based on name. This is a bit of a kludge thanks to the way that Python module resolution hooks work, as it's not clear exactly which namespace the module is intended to be loaded from at runtime as it's not passed to the resolver. Down the track we may need to get smarter with the resolver so that we have a per-module resolver (ie. a tree of resolvers).
