Auto merge of #131 - conradkleinespel:patch-2, r=SimonSapin
Auto merge of #131 - conradkleinespel:patch-2, r=SimonSapin

Adds docs about query string decoding

Hello,

I was [looking](https://twitter.com/kleinespel/status/643462183783923712) for a library to decode a query string from a URL, when I hadn't realised `url::form_urlencoded::parse` did just that.

I hope this little doc addition makes things a bit more clear.

Best regards,
Conrad

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cGuille/rust-url,servo/rust-url,cGuille/rust-url,servo/rust-url