Auto merge of #175 - nox:unbump-heapsize, r=SimonSapin

Unbump heapsize_plugin to 0.1.0

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Cargo.toml

@@ -1,7 +1,7 @@
 [package]
 
 name = "url"
-version = "0.5.6"
+version = "0.5.7"
 authors = [ "Simon Sapin <simon.sapin@exyr.org>" ]
 
 description = "URL library for Rust, based on the WHATWG URL Standard"
@@ -33,7 +33,7 @@ version = ">=0.1.1, <0.4"
 optional = true
 
 [dependencies.heapsize_plugin]
-version = "0.1.4"
+version = "0.1.0"
 optional = true
 
 [dependencies.encoding]