Auto merge of #96 - nox:heapsize, r=Ms2ger

Allow heapsize 0.3

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Author: bors-servo

Cargo.toml

@@ -1,7 +1,7 @@
 [package]
 
 name = "cssparser"
-version = "0.5.2"
+version = "0.5.3"
 authors = [ "Simon Sapin <simon.sapin@exyr.org>" ]
 
 description = "Rust implementation of CSS Syntax Level 3"
@@ -25,7 +25,7 @@ version = "0.6.5"
 optional = true
 
 [dependencies.heapsize]
-version = ">=0.1.1, <0.3.0"
+version = ">=0.1.1, <0.4.0"
 optional = true
 
 [dependencies.heapsize_plugin]