Remove URI::URL

Switch away from deprecated URI::URL to all URI.pm (which URI::URL is just a wrapper around).

URI works a little differently than URI::URL which might cause some backwards compatibility issues.  The biggest is that URI::URL would canonicalize the URL (ex. "HTTP://FOO.com" becomes "http://foo.com/").  This lost the original formatting, the URI behavior is better.  You can get the canonicalized version with `$uri->canonical`.

This is for #5