Breaking: YAML config `ip_view_expiration` is renamed `view_expiration`
Breaking: Views are taken into account after 10 seconds instead of 30
seconds (can be changed in YAML config)
Purpose of this commit is to get closer to other video platforms where
some platforms count views on play (mux, vimeo) or others use a very low
delay (instagram, tiktok)
We also want to improve the viewer identification, where we no longer
use the IP but the `sessionId` generated by the web browser. Multiple
viewers behind a NAT can now be able to be identified as independent
viewers (this method is also used by vimeo or mux)
