New API for `configure.reporters` and `--reporters` argument

[Julien-R44]

Linked to #23

Refactor

• Moved what is related to CLI parsing into its own file
• Moved what is related to configuration and configuration normalization to its own file

What has been added

• a --reporters arguments
• New API for configure.reporters property, but backward compatible. the configure.reporters.defaults property is typesafe and and based on what configure.reporters.list contains.

To keep the API retro-compatible, but also to keep the code simple, I made some functions to "normalize" the configuration. So even if the old API is used, then this function will convert that into the same format as the new one. ( with the defaults and list properties. )

If the old API is used, then all reporters are activated by default

The --reporters flag overrides the reporters.defaults property

To merge this PR it will be necessary in priority to merge this one: https://github.com/japa/core/pull/65 Then update @japa/core

Let me know if anything seems unclear or if anything needs to be changed