Auto merge of #153 - servo:jdm-patch-1, r=Manishearth

Publish 0.6.10.

This incorporates #144, #152, #150, and #151, which should all be minor version updates according to semver.

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Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "smallvec"
-version = "0.6.9"
+version = "0.6.10"
 authors = ["Simon Sapin <[email protected]>"]
 license = "MIT/Apache-2.0"
 repository = "https://github.com/servo/rust-smallvec"