nvda

a3783595 - nvda.pyw, setup.py: When running from source, add miscDeps/python to the Python module search path.

nvda.pyw, setup.py: When running from source, add miscDeps/python to the Python module search path. The real code is in the sourceEnv module, which is imported as needed. This is in preparation for moving Python dependencies into the misc deps Git submodule.