Define Quartz scheduler beans inside the add-on

[gorbunkov]

The search add-on requires a scheduler for processing the indexing queue. Currently we recommend users to add the spring-boot-starter-quartz to their project and to define all quartz beans in projects. Probably we can simplify the process by doing the following:

1. Define a compile-time dependency to the quartz in the add-on

2. Create an auto-configuration that will instantiate required quartz beans if quartz is in the classpath and if a special application property is set, e.g. jmix.search.useDefaultIndexingQueueProcessingQuartzConfiguration is true (default behavior).

The Quartz beans:

public class IndexingQueueProcessingJob implements Job {

    @Autowired
    private IndexingQueueManager indexingQueueManager;

    @Override
    public void execute(JobExecutionContext context) throws JobExecutionException {
          indexingQueueManager.processNextBatch();
    }
}

@Bean
JobDetail indexingQueueProcessingJob() {
	return JobBuilder.newJob()
			.ofType(IndexingQueueProcessingJob.class)
			.storeDurably()
			.withIdentity("IndexingQueueProcessing")
			.build();
}

@Bean
Trigger indexingQueueProcessingTrigger() {
	return TriggerBuilder.newTrigger()
			.forJob(indexingQueueProcessingJob())
			.startNow()
			.withSchedule(CronScheduleBuilder.cronSchedule("0/5 * * * * ?"))
			.build();
}

3. The cron expression should be taken from the application property, e.g. jmix.search.indexingQueueProcessingCron