t3.cnf: a better example of unsat formula

Signed-off-by: Diego Giovane Pasqualin <dpasqualin@c3sl.ufpr.br>
dpll.js: Fix* graph of unsat formula

* Some unsat nodes are not getting the UNSAT children node.

Signed-off-by: Diego Giovane Pasqualin <dpasqualin@c3sl.ufpr.br>