Auto merge of #174 - TheKK:version_bump, r=nox

Version bump to 0.2.30

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Author: bors-servo

Cargo.toml

@@ -1,7 +1,7 @@
 [package]
 
 name = "string_cache"
-version = "0.2.29"
+version = "0.2.30"
 authors = [ "The Servo Project Developers" ]
 description = "A string interning library for Rust, developed as part of the Servo project."
 license = "MIT / Apache-2.0"