Feature Request: Make default prefixes configurable

[theppi]

Prefixes are by now configurable only for every individual message.

It would be nice to be able to configure the default prefixes used in a buntstift instance for a specific level (e.g. increasing the indentation) via configuration.

Perhaps something like that:

buntstift.configure(
  buntstift.getConfiguration().
    withPrefixes({
      info: 'INFO:'
    })
);