Auto merge of #78 - servo:bump, r=jdm

Bump to 0.3.9

r? @nox

cc @sfackler

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Author: bors-servo

Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "heapsize"
-version = "0.3.8"
+version = "0.3.9"
 authors = [ "The Servo Project Developers" ]
 description = "Infrastructure for measuring the total runtime size of an object on the heap"
 license = "MPL-2.0"