Creates any directories required for Engineer to function if they don't already exist.

def create_required_directories(self):
        """Creates any directories required for Engineer to function if they don't already exist."""
        required = (self.CACHE_DIR,
                    self.LOG_DIR,
                    self.OUTPUT_DIR,
                    self.ENGINEER.JINJA_CACHE_DIR,)

        for folder in required:
            ensure_exists(folder, assume_dirs=True)