Auto merge of #231 - notriddle:master, r=jdm

Increment version number.

(this will need to be pushed to Crates.IO, of course)

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Author: bors-servo

Cargo.toml

@@ -1,7 +1,7 @@
 [package]
 
 name = "layers"
-version = "0.2.2"
+version = "0.2.3"
 authors = ["The Servo Project Developers"]
 license = "MIT/Apache-2.0"