Add a development mode

#### Support plan

* *is this issue currently blocking your project?* (yes/no): no
* *is this issue affecting a production system?* (yes/no): no

#### Context

* *node version*: N/A
* *module version*: latest
* *environment* (e.g. node, browser, native): node
* *used with* (e.g. hapi application, another framework, standalone, ...): hapi
* *any other relevant information*:

#### What problem are you trying to solve?

As discussed among TSC members, it would be nice to have a development mode for the logs. It would be `false` by default but once enabled it would print to stdout a bunch of useful information while developing:

* Errors
* Responses:
* Status code
* Path
* Method
* Response time

All with a nice format. Perhaps if we even want to get fancy we could use `chalk` or something like that for pretty colors.

#### Do you have a new or modified API suggestion to solve the problem?

I suggest we had a new root field in the plugin registration options:

```js
{
dev: false
}
```

This field would be false by default. Another name for the field could be `development` if we prefer that.