Increment version from 0.4.0 to 0.5.0.

Upgrade of serde and other dependencies.

Minimum supported Rust version is now 1.13.0 and no
longer 1.8.0.

Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "serde_cbor"
-version = "0.4.0"
+version = "0.5.0"
 authors = ["Pyfisch <[email protected]>"]
 repository = "https://github.com/pyfisch/cbor"
 documentation = "http://pyfisch.github.io/cbor/serde_cbor/index.html"