bump version to v0.1.3; update edition to 2021

Author: vadixidav

Cargo.toml

@@ -1,8 +1,8 @@
 [package]
 name = "header-vec"
-version = "0.1.3-alpha.0"
+version = "0.1.3"
 authors = ["Geordon Worley <[email protected]>"]
-edition = "2018"
+edition = "2021"
 description = "Vector with user-specified header, length, capacity, and array elements all stored on the heap together"
 documentation = "https://docs.rs/header-vec/"
 repository = "https://github.com/rust-cv/header-vec"