Now works with cross table formulas.

@markerickson-wf @andrewallen-wf @beaulyddon-wf @robertkluin-wf @jasonaguilon-wf 

This is somewhat ugly and I obviously need to do some cleanup, but this code actually enables cross table formulas that appear in the form tablename:A1:C3.  It will do its initial calculation and update correctly.  Next step is stubbing out a datastore.