src/node-cron.js
function schedule(expression, func, options) {
        let task = createTask(expression, func, options);
        storage.save(task);
        return task;
    }
function schedule(expression, func, options) {
        let task = createTask(expression, func, options);
        storage.save(task);
        return task;
    }
function schedule ( expression , func , options ) { let task = createTask ( expression , func , options ) ; storage . save ( task ) ; return task ; }
Creates a new task to execute given function when the cron
expression ticks.

@param {string} expression - cron expression.
@param {Function} func - task to be executed.
@param {Object} options - a set of options for the scheduled task:
- scheduled <boolean>: if a schaduled task is ready and running to be
performed when the time mach with the cron excpression.
- timezone <string>: the tiemzone to execute the tasks.

Example:
{
"scheduled": true,
"timezone": "America/Sao_Paulo"
}

@returns {ScheduledTask} update function.
Creates a new task to execute given function when the cron expression ticks .