Analytical logging for incoming task requests

Wrote a new method to analyze incoming task requests.  This
analytical data can be found in the header of each request and
can be useful for debugging task queues and monitoring performance.
Created test files for _log_task_info

Things this tests for.
- all the expected headers are found
- none of the expected headers are found
- expected headers are found while ignoring unrealated headers
Added missing comment to handler test
Updated arguments on logging debug
Made a stylistic change with arguments for logging debug.
Then updated tests to handle this change in expected arguments.
Flake8 style update for test__init.py
Log_task_info outputs more useful data

Made changes to the headers we are logging in tasks
requests. We found queuename and taskname were redundantent.
We also found we should log the time that the request was made.
Updated log_task_info tests to fit new spec

This includes all the changes in values we are logging.
Merge pull request #94 from robertsheehy-wf/logging-task-info

Analytical logging for incoming task requests