refactor: default event parameters

[Valazan]

Currently. all the filters parameters must be set by hand. We need some defaults value that let eveything to work out of the box.

In particular:

 range: 
              {
                    unit: 'block',
                    from: 0,
                    to: (bestBlock as CompressedBlockDetail).number
                }

and limit, must be set to default values.

Otherwise, we are not able to filter properly the events.