implement allowed-http-host-header

Related #314

Mainly inspired by django implementation https://docs.djangoproject.com/en/3.2/ref/settings/#allowed-hosts

This protects against HTTP Host header attacks

It is working as expected on my local tests.

The MR is on draft for now to see if the tests are ok.

Useful warnings are printed when the user haven't sent the option:

Don't hesitate if you want to change the formulation I wasn't very inspired.