update simple traffic light AF3 tour for OCRA contract
Context: OCRA contracts
Issue: The project and tutorial both contain the formula “!A OR B” for “A implies B”. It is so because implication was not supported as an operator. Now it is available and the tutorial and project should be updated accordingly.
Scope: It affects only OCRA contracts. Nothing else.
(from redmine: issue id 3260, created on 2018-01-31)