Rewrite rule that applies the distributive law to convert expressions to CNF.
See: https://en.wikipedia.org/wiki/Distributive_property
Applies the transformations:
A OR (B AND C) = (A OR B) AND (A OR C)(A AND B) OR C = (A OR C) AND (B OR C)
This transformation pushes OR operations inside AND operations, which is necessary for achieving Conjunctive Normal Form (CNF).