Code cleanup

This includes removing the custom zlib module which just caused maintenance
effort without actually being useful.

Made entire codebase linter compatible.
However, py3 still shows some errors, whose fix should be easy enough

Author: Byron

async/__init__.py

@@ -4,44 +4,7 @@
 # the New BSD License: http://www.opensource.org/licenses/bsd-license.php
 """Initialize the multi-processing package"""
 
-#{ Initialization
-def _init_atexit():
-    """Setup an at-exit job to be sure our workers are shutdown correctly before
-    the interpreter quits"""
-    import atexit
-    from . import thread
-    atexit.register(thread.do_terminate_threads)
-
-def _init_signals():
-    """Assure we shutdown our threads correctly when being interrupted"""
-    import signal
-    from . import thread
-    import sys
-
-    prev_handler = signal.getsignal(signal.SIGINT)
-    def thread_interrupt_handler(signum, frame):
-        thread.do_terminate_threads()
-        if isinstance(prev_handler, collections.Callable):
-            prev_handler(signum, frame)
-            raise KeyboardInterrupt()
-        # END call previous handler
-    # END signal handler
-    try:
-        signal.signal(signal.SIGINT, thread_interrupt_handler)
-    except ValueError:
-        # happens if we don't try it from the main thread
-        sys.stderr.write("Failed to setup thread-interrupt handler. This is usually not critical")
-    # END exception handling
-
-
-#} END init
-
-_init_atexit()
-_init_signals()
-
-
 # initial imports
 from .task import *
 from .pool import *
 from .channel import *
-import collections

async/channel.py

@@ -24,7 +24,7 @@
 import threading
 import sys
 
-__all__ = ('Channel', 'SerialChannel', 'Writer', 'ChannelWriter', 'CallbackChannelWriter',
+__all__ = ( 'Channel', 'SerialChannel', 'Writer', 'ChannelWriter', 'CallbackChannelWriter',
             'Reader', 'ChannelReader', 'CallbackChannelReader', 'mkchannel', 'ReadOnly',
             'IteratorReader', 'CallbackReaderMixin', 'CallbackWriterMixin')