Auto merge of #168 - nox:heapsize, r=jdm

Allow heapsize 0.3

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Cargo.toml

@@ -1,7 +1,7 @@
 [package]
 
 name = "url"
-version = "0.5.4"
+version = "0.5.5"
 authors = [ "Simon Sapin <simon.sapin@exyr.org>" ]
 
 description = "URL library for Rust, based on the WHATWG URL Standard"
@@ -29,7 +29,7 @@ serde_serialization = ["serde"]
 heap_size = ["heapsize", "heapsize_plugin"]
 
 [dependencies.heapsize]
-version = ">=0.1.1, <0.3"
+version = ">=0.1.1, <0.4"
 optional = true
 
 [dependencies.heapsize_plugin]