Add a place to put record validation in SObjectTriggerHandler

[jongpie]

A constant problem with Salesforce is determining where to put Apex validation checks for a record during a trigger/save. Nebula should have a place to put these types of validation - best practice says it should be executed in an after trigger, so that seems like a good place to start.

My initial thought is to create an interface like the one below, then make a spot for it in SObjectTriggerHandler so that the validator can be called during trigger execution.

public interface ISObjectValidator {
    void validate();
}