Bump version to v0.4.4

CHANGELOG.md

-# 0.4.3 (April, 30, 2017)
+# 0.4.4 (May 26, 2017)
+
+* Add serde support behind feature flag
+* Add `extend_from_slice` on `Bytes` and `BytesMut`
+* Add `truncate` and `clear` on `Bytes`
+* Misc additional std trait implementations
+* Misc performance improvements
+
+# 0.4.3 (April 30, 2017)
 
 * Fix Vec::advance_mut bug
 * Bump minimum Rust version to 1.15
 * Misc performance tweaks
 
-# 0.4.2 (April, 5, 2017)
+# 0.4.2 (April 5, 2017)
 
 * Misc performance tweaks
 * Improved `Debug` implementation for `Bytes`

Cargo.toml

 [package]
 
 name          = "bytes"
-version       = "0.4.3"
+version       = "0.4.4"
 license       = "MIT"
 authors       = ["Carl Lerche <me@carllerche.com>"]
 description   = "Types and traits for working with bytes"