Version bump to v12.0 (#77)

Author: AgeManning

Cargo.toml

@@ -2,7 +2,7 @@
 name = "enr"
 authors = ["Age Manning <[email protected]>"]
 edition = "2018"
-version = "0.11.1"
+version = "0.12.0"
 description = "Rust implementation of Ethereum Node Record (ENR) EIP778"
 readme = "./README.md"
 keywords = ["ethereum", "enr", "record", "EIP778", "node"]