Auto merge of #183 - servo:uuid, r=SimonSapin

Update uuid.

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Cargo.toml

@@ -1,7 +1,7 @@
 [package]
 
 name = "url"
-version = "0.5.7"
+version = "0.5.8"
 authors = [ "Simon Sapin <simon.sapin@exyr.org>" ]
 
 description = "URL library for Rust, based on the WHATWG URL Standard"
@@ -45,7 +45,7 @@ version = ">=0.6.1, <0.8"
 optional = true
 
 [dependencies]
-uuid = "0.1.17"
+uuid = { version = "0.2", features = ["v4"] }
 rustc-serialize = "0.3"
 unicode-bidi = "0.2.3"
 unicode-normalization = "0.1.2"