Add README

Package.swift

@@ -6,8 +6,8 @@ import PackageDescription
 let package = Package(
     name: "wg-go-apple",
     platforms: [
-        .macOS(.v12),
         .iOS(.v15),
+        .macOS(.v12),
         .tvOS(.v17)
     ],
     products: [

README.md

@@ -0,0 +1,9 @@
+![iOS 15+](https://img.shields.io/badge/iOS-15+-green.svg)
+![macOS 12+](https://img.shields.io/badge/macOS-12+-green.svg)
+![tvOS 17+](https://img.shields.io/badge/tvOS-17+-green.svg)
+
+# wg-go
+
+This Swift package provides a binary version of wg-go, built with the scripts of [the official WireGuard repository][repo-wg-go].
+
+[repo-wg-go]: https://github.com/WireGuard/wireguard-apple/tree/master/Sources/WireGuardKitGo