Added VisionOS support (#12)

* Update Package.swift

* Added tvOS

* Update Package.swift

* Update Package.swift

Author: davidhakki

Package.swift

@@ -1,4 +1,4 @@
-// swift-tools-version:5.5
+// swift-tools-version:5.9
 // The swift-tools-version declares the minimum version of Swift required to build this package.
 
 import PackageDescription
@@ -7,7 +7,8 @@ let package = Package(
     name: "Markdown",
     platforms: [
         .iOS(.v14),
-        .macOS(.v11)
+        .macOS(.v11),
+        .visionOS(.v1),
     ],
     products: [
         // Products define the executables and libraries a package produces, and make them visible to other packages.

Sources/Markdown/Markdown.swift

@@ -4,7 +4,7 @@ import WebKit
 #if os(OSX)
     import AppKit
     public typealias ViewRepresentable = NSViewRepresentable
-#elseif os(iOS)
+#else
     import UIKit
     public typealias ViewRepresentable = UIViewRepresentable
 #endif

Sources/Markdown/MarkdownWebView.swift

@@ -10,7 +10,7 @@ import WebKit
 #if os(OSX)
     import AppKit
     public typealias CustomView = NSView
-#elseif os(iOS)
+#else
     import UIKit
     public typealias CustomView = UIView
 #endif