Swift: Update to package manager 5.1

swift/Sources/GildedRoseApp/main.swift

@@ -0,0 +1,31 @@
+import GildedRose
+
+let items = [
+    Item(name: "+5 Dexterity Vest", sellIn: 10, quality: 20),
+    Item(name: "Aged Brie", sellIn: 2, quality: 0),
+    Item(name: "Elixir of the Mongoose", sellIn: 5, quality: 7),
+    Item(name: "Sulfuras, Hand of Ragnaros", sellIn: 0, quality: 80),
+    Item(name: "Sulfuras, Hand of Ragnaros", sellIn: -1, quality: 80),
+    Item(name: "Backstage passes to a TAFKAL80ETC concert", sellIn: 15, quality: 20),
+    Item(name: "Backstage passes to a TAFKAL80ETC concert", sellIn: 10, quality: 49),
+    Item(name: "Backstage passes to a TAFKAL80ETC concert", sellIn: 5, quality: 49),
+    // this conjured item does not work properly yet
+    Item(name: "Conjured Mana Cake", sellIn: 3, quality: 6)]
+
+let app = GildedRose(items: items);
+
+var days = 2;
+if (CommandLine.argc > 1) {
+    days = Int(CommandLine.arguments[1])! + 1
+}
+
+
+for i in 0..<days {
+    print("-------- day \(i) --------");
+    print("name, sellIn, quality");
+    for item in items {
+        print(item);
+    }
+    print("");
+    app.updateQuality();
+}