Implement worker_abort server hook

Also update the manifest command to pass the config file in as a parameter
and modify the logs agent to start shipping the error log to cloudwatch

gunicorn_config.py

@@ -0,0 +1,5 @@
+def worker_abort(worker):
+    worker.log.info("worker received ABORT")
+    import sys, traceback
+    for threadId, stack in sys._current_frames().items():
+        worker.log.info(''.join(traceback.format_stack(stack)))