Add new settings for using flaresolverr

[Tsuna77]

Flaresolverr project is a cloudflare automatic bypasser.

With flaresolver you can ask for a session that you can use for your scripts.

It's an API and not a proxy, so it's need a specific developement. but can (if the user have it installed) allow to automaticly bypass cloudflare without asking to manualy update challenge cookies.

[ronny1982]

There is HakuNeko Assistant which already does the job.