Spoof/Change User-Agent

[jonzlin95]

Some sites don't play well without User-Agents (e.g. ESPN).

HTTPoison by default sends hackney which is blocked, so it could be useful to set it to

["User-Agent": "Elixir"] or some similar string to bypass these problems.

[Anonyfox]

Why not faking a typical iPhone signature? I think some sites whitelist on UA strings

[jonzlin95]

That could work too. Maybe it would be useful to add a way to pass in a User Agent to the Scrape.X function calls. I notice that you already have fetch(url, html_headers \ []), and that could just be passed onto the next set of functions.

I can make a simple PR for this.