turn FlowByActivity and FlowBySector into classes, where functions are created specifically for each class
create FlowBy class for functions used in both FBA and FBS classes
FBS yamls revised to work for unlimited recursive and sequential attribution methods
updates to Paths, which require most up-to-date versions of fedefelmflowlist, esupy, stewi
new github action to generate a single FBA
source_catalog.yaml updated to include FBS info. Specify if data is in FBA or FBS format. 'activity_schema' can be year-dependent. rename sector_aggregation_levels from "aggregated" and "disaggregated" to "flat" and "Parent-completeChild" and "parent-incompleteChild".
Major updates:
Features that are lost: