refactor github lister into something more generic
Code from the old github lister has been moved, genericized, and extended into lister and model base classes. Hopefully it will make contribution of new listers easier.
There are also some preliminary unit tests included which stub out scheduler and database accesses.
This is currently in DLSGH by early suggestion. DLSGH will probably be renamed to DLS<something_else_more_generic>.
Test Plan
make test add more tests rinse repeat
currently does not test integration with scheduler or storage
Migrated from D165 (view on Phabricator)