Start multiple scrapers at once

[kinoute]

Right now, we can only scrap one website at a time.

A user could pass multiple websites like:

• —website "blubeaver film-grab" ;
• —website "blubeaver, film-grab" (comma separated) ;
• —website blubeaver —website film-grab.
• etc.

An option to scrap everything at the same time (all) could also be added.