Test code for IRIS datalog evaluation.
Refactor out static rule parsing.
Factor out SQL AST dynamic fact generation.
Update translation rule interface:
*WARN*: This breaks the previous rule implementation as of this commit.
Datalog rules work in progress.
Remove old rule algorithm rules.
Revise rule interfaces to ease state passing.
JoinLabelRule2 now almost caught up with previous JoinLabelRule.
Some additional utility methods and classes.