start work on flows branch, need to return to master to fix bug
but first, commit
fixed project reference in contribution tables
create workflow order tests
and make enough changes so they pass
add some helper methods,
add some test assertions to test them,
fix some test-discovered bugs
deal with flow todos
fix bugs found by new test_commitment_change_propagation
replace several leftover resource_type.producing_commitments()
 with commitment.associated_producing_commitments()
and replace some leftover independent_demand with order_item
Merge branch 'flows'

Conflicts:
	valuenetwork/valueaccounting/models.py
remove some leftover print statements
Merge branch 'master' of git@github.com:valnet/valuenetwork.git