Use cURL follow-redirects instead of manual looping forever.

Use cURL follow-redirects instead of manual looping forever. Closes #18. Closes #5.

I also moved the logging and header status setting up above the error checking.

I changed the default client to cURL since it generally works faster, has better error reporting at this point, and is recommended.

I changed the default timeout to 10 seconds since some slow international sites take more than 5 seconds to respond.