Fix handling Googlevideo URLs returning redirects

[Kethsar]

It seems direct googlevideo.com URLs can return plain text with intent to have you redirect, instead of redirecting you itself.

• Check the content-type header for text/plain and assume it's a redirect URL.
• Potentially recursively call the function that checks up to X times until a working URL is given.
• Move the sq param to the end of the URL instead of truncating the rest of the URL. Could end up never retrieving video or audio.

[Kethsar]

I've never seen this outside of the one time that caused me to open this ticket, and I think it may have been in part from trying to mess with the url while testing stuff in the browser.