fix: refactor code so most things work without sqlalchemy

also refactor tests to help ensure that remains true

Assign extra import handler kwargs before loading the importers

e.g. for CORE importers which can target different DB and therefore
the set of importers must vary by DB

Disable some tests, pending new mock

should fix someday..no time to do it today

Move tests out of the installed package set

this seems to be better practice. from what i can tell this is a
clean move with no breakage.. and built package files no longer seem
to include test modules