SSA-6324: proof of concept -- running tests in Docker container. These tests all pass at the pytest command line -AND- inside a  container. scode project updater code removed -- doesn't work, and will be merged in from archive eventually.

methods based on the architecture diagrams; copied null capability
implementation from wksp0

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

SSA-6607: much refactoring of data fetcher and components for testability; lots of tests complete, lots more TODO

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