Auto merge of #188 - nox:bump, r=mbrubeck

Bump version to 0.12.0

#187

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Author: bors-servo

Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "euclid"
-version = "0.11.2"
+version = "0.12.0"
 authors = ["The Servo Project Developers"]
 description = "Geometry primitives"
 documentation = "https://docs.rs/euclid/"