Auto merge of #110 - mbrubeck:bump, r=Manishearth

Version 0.6.4

Change log:

* Extend the `smallvec!` macro to work with non-`Copy` items (#107)
* Improve the `Debug` formatting implementation (#109)

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Author: bors-servo

Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "smallvec"
-version = "0.6.3"
+version = "0.6.4"
 authors = ["Simon Sapin <[email protected]>"]
 license = "MIT/Apache-2.0"
 repository = "https://github.com/servo/rust-smallvec"