Refactoring for better logging (#4444)

* Move colored_logging.py to log.py

* Add atexit.register code to util

* Add tests for atexit_register

* Copy except_hook to log

* Add pre_arg_setup

* move setup_log_file_handler to log.py

* Add post_arg_setup

* move changes to main

* Undo changes to MainTest

* s/pre_arg_setup/pre_arg_parse_setup

* s/post_arg_setup/post_arg_parse_setup

certbot/reporter.py

@@ -3,7 +3,6 @@ from __future__ import print_function
 
 import collections
 import logging
-import os
 import sys
 import textwrap
 
@@ -16,11 +15,6 @@ from certbot import util
 
 logger = logging.getLogger(__name__)
 
-# Store the pid of the process that first imported this module so that
-# atexit_print_messages side-effects such as error reporting can be limited to
-# this process and not any fork()'d children.
-INITIAL_PID = os.getpid()
-
 
 @zope.interface.implementer(interfaces.IReporter)
 class Reporter(object):
@@ -60,19 +54,6 @@ class Reporter(object):
         self.messages.put(self._msg_type(priority, msg, on_crash))
         logger.debug("Reporting to user: %s", msg)
 
-    def atexit_print_messages(self, pid=None):
-        """Function to be registered with atexit to print messages.
-
-        :param int pid: Process ID
-
-        """
-        if pid is None:
-            pid = INITIAL_PID
-        # This ensures that messages are only printed from the process that
-        # created the Reporter.
-        if pid == os.getpid():
-            self.print_messages()
-
     def print_messages(self):
         """Prints messages to the user and clears the message queue.