Auto merge of servo#92 - nox:bump-heapsize, r=Ms2ger

Allow heapsize 0.2.z

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Author: bors-servo

Cargo.toml

@@ -23,7 +23,7 @@ optional = true
 optional = true
 
 [dependencies.heapsize]
-version = "0.1.1"
+version = ">=0.1.1, <0.3.0"
 optional = true
 
 [dependencies.heapsize_plugin]