wf_monitor to use new amqp_helpers setup; updated wf_monitor tests;
updated WorkflowEventSchema to accept a string in the timestamp field
instead of a datetime (we could probably change this, but this is how
it's set up for now)

originally going to use a singleton pattern but ran into issues with
that)

all necessary fields have been updated to reflect naming changes

Hopefully final changes to setup.py files regarding package name changes; renamed a amqp_helpers dir to channels

Made amqp_helpers directory structure match the other subprojects. Made some small changes to monitor.py and test_monitor.py

Added __str__ and __repr__ methods to WorkflowMonitor; small updates to same methods in WorkflowEvent

Changed import statements to break local testing but fix automatic conda build testing. I'm not sure how to resolve the different import needs.

SSA-6324: refactored prop setter for testability and created tests; added script to run all tests in data repo