Move to named parameters

[jsumners]

We should move to named parameter functions in the next release. For example, with #1576 we tacked on another parameter to the level-change event:

pino/docs/api.md

Lines 1027 to 1032 in 085401b

	logger.on('level-change', function (lvl, val, prevLvl, prevVal, instance) {
	if (logger !== instance) {
	return
	}
	console.log('%s (%d) was changed to %s (%d)', prevLvl, prevVal, lvl, val)
	})

While the function signature of an event listener is easier to understand than one someone invokes themselves, I still think named parameters is a better experience.

[jsumners]

@debadutta98 I'm sorry. I didn't realize @mcollina had marked this a good first issue. Still, as noted in #1583, this issue is not just about the single level-change signature. We need to scour the code for all functions have difficult signatures and update them where feasible (noting that it may not be feasible in certain hot paths due to destructuring perf penalties; in which case we should document the code).