URL encode request URIs by default

[jypma]

If there are any non-ASCII characters in the request URI, curl will send those through in raw UTF-8 form by default. That is almost never what you'd want, since all server frameworks will expect non-ASCII characters to be percent-encoded.

The built-in url-encode-url function does exactly that, so we pass our request URI through it.

Please let me know if this should be a switch instead; I couldn't think of a case where you wouldn't want this.

[xqliu]

Dear,

Is there any chance this PR been merged ? I think that's really very reasonable to send encode URL.

Thanks.