Fix cannot to disable spring counter

[timic]

Service interceptor from plugin is a bit buggy. So I want to disable it. But I can't.

This is because counter's displayed property is will be set later when MonitoringFilter will be initialized.

It seems to be better to use isUsed method which check counter availability in context init-params.

[evernat]

I think that we can't call "isUsed" there, because it will never return true if an instance of MonitoringSpringInterceptor is not created.

Would ! Parameters.isCounterHidden("spring") be better than SPRING_COUNTER.isDisplayed() ?

[timic]

Yes, it is. I'll update pull request.

[evernat]

Thanks timic