added MANIFEST to .gitignore
Switch all debugging print statements to logging.debug()
Handle errors when reading or writing to channels, and when pickling
Add InternalClientError and InternalServerError
Handle importing of builting modules (e.g. "import sys")
Add unittests for generators, lambdas, files, byvalue()
Add unittests that wrap items from the sys and os modules
Make unittests run each testcase in a separate process by default
Prioritize TODOs