Rework ConsoleHandler to use native console methods

**Is your feature request related to a problem? Please describe.**

When using the `log` module with Deno Deploy, the output is not "native" in the dashboard:


**Describe the solution you'd like**

Deno Deploy provides a clean UI for logs outputed with the `debug`, `info`, `warn`, `error` methods, what about using those by default in `ConsoleHandler`?


**Describe alternatives you've considered**

The `ConsoleHandler` can be useful but in a terminal, what about renaming it `TerminalHandler` and creating a new `ConsoleHandler`?

- `TerminalHandler`: always outputs with `console.log` and formats data by itself, like the current `ConsoleHandler`.
- `ConsoleHandler`: outputs with the appropriate `console.*` methods, lets Deno Deploy handle the formatting.

The only drawback I can see is the missing `critical` method in the native `console` API.