Auto merge of #131 - mbrubeck:bump, r=jdm

Version 0.6.6

Changes in this release:

* Fix possible over-allocation in `from_slice` (#122)
* Optional nightly-only `specialization` feature for `from_slice` optimization (#123)
* New `from_raw_parts` constructor (#130)
* Documentation and testing improvements (#125, #129)

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Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "smallvec"
-version = "0.6.5"
+version = "0.6.6"
 authors = ["Simon Sapin <simon.sapin@exyr.org>"]
 license = "MIT/Apache-2.0"
 repository = "https://github.com/servo/rust-smallvec"