Make Swift 6 tools version more generic and add support for Swift 5.9 to support Swift 5 mode

Author: toastersocks

Package.swift

@@ -1,4 +1,4 @@
-// swift-tools-version: 6.1
+// swift-tools-version: 6
 // The swift-tools-version declares the minimum version of Swift required to build this package.
 
 import PackageDescription

Package@swift-5.9.swift

@@ -0,0 +1,35 @@
+// swift-tools-version: 5.9
+// The swift-tools-version declares the minimum version of Swift required to build this package.
+
+import PackageDescription
+
+let package = Package(
+    name: "MultiPicker",
+    platforms: [
+        .iOS(.v16),
+        .macOS(.v13),
+        .watchOS(.v9)
+    ],
+    products: [
+        // Products define the executables and libraries a package produces, and make them visible to other packages.
+        .library(
+            name: "MultiPicker",
+            targets: ["MultiPicker"]),
+    ],
+    dependencies: [
+        .package(url: "https://github.com/toastersocks/Helpers.git", from: "0.0.0"),
+        .package(url: "https://github.com/toastersocks/Flow.git", from: "1.2.3"),
+        // Dependencies declare other packages that this package depends on.
+        // .package(url: /* package url */, from: "1.0.0"),
+    ],
+    targets: [
+        // Targets are the basic building blocks of a package. A target can define a module or a test suite.
+        // Targets can depend on other targets in this package, and on products in packages this package depends on.
+        .target(
+            name: "MultiPicker",
+            dependencies: ["Helpers", "Flow"]),
+        .testTarget(
+            name: "MultiPickerTests",
+            dependencies: ["MultiPicker"]),
+    ]
+)