World Channels Devlog 9.

Filtered new channels and updated categories to maintain country placements. Also continued to update descriptions in README.md and App.tsx as well as updating checking stream offline/online ability logic as seen below:

        if (contentType.includes('text/html')) {
          if (hasMediaExtension) {
            // It asked for a media file but got a webpage. This is a dead link/error page.
            req.destroy();
            return resolve(false);
          } else {
            // It asked for an extensionless URL and got a webpage. Trust it as a valid Iframe embed.
            req.destroy();
            return resolve(true);
          }
        }