Auto merge of servo#204 - servo:bump, r=SimonSapin

Breaking version bump to account for servo#203.

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Author: bors-servo

Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "cssparser"
-version = "0.22.1"
+version = "0.23.0"
 authors = [ "Simon Sapin <simon.sapin@exyr.org>" ]
 
 description = "Rust implementation of CSS Syntax Level 3"