Auto merge of #263 - jdm:xml5version, r=SimonSapin

Bump xml5ever version.

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Author: bors-servo

xml5ever/Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "xml5ever"
-version = "0.4.2"
+version = "0.4.3"
 description = "Push based streaming parser for xml"
 homepage = "https://github.com/servo/html5ever/blob/master/xml5ever/README.md"
 documentation = "https://docs.rs/xml5ever/"