Add Label Option

Description

Allow adding labels to Observables to help identify them

Example

// We can add a label to the logs:

const obs$ = of('my test value');
obs$.pipe(debug('Obserable A')).subscribe();

// OUTPUT:
// Obserable A    my test value

// We can label it using the config object syntax:
const obs$ = of('my test value');
obs$.pipe(debug({ label: 'Obserable A' })).subscribe();

// OUTPUT:
// Obserable A    my test value

// However, if we add a label and custom notification handlers,
// we will not get the label in the logs by default:
const obs$ = of('my test value');
obs$
  .pipe(
    debug({
      label: 'Obserable A',
      next: (value) => console.log(value),
    })
  )
  .subscribe();

// OUTPUT:
// my test value