Auto merge of #163 - pcwalton:0.61.4, r=jdm

Bump version to 0.61.4

r? @jdm

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Author: bors-servo

Cargo.toml

@@ -2,7 +2,7 @@
 name = "mozjs_sys"
 description = "System crate for the Mozilla SpiderMonkey JavaScript engine."
 repository = "https://github.com/servo/mozjs/"
-version = "0.61.3"
+version = "0.61.4"
 authors = ["Mozilla"]
 links = "mozjs"
 build = "build.rs"