Codable utility types implemented so far

These are all used from Bestiary; and consistent of Page, Source (otherSources, alternateSources), Edition, Reprint (reprintedAs), Speed, CreatureType, Alignment, Size, and Proficiency (proficiencyLevel).

Also add Tag, which is a common type-like used in Bestiary but didn't get its own $defs.

Trying to make the resulting types as ergonmically Swift-like as possible, while still supporting the full 5eTools schema.

Author: keybuk

Package.resolved

@@ -15,11 +15,19 @@ let package = Package(
             targets: ["FifthEdition"]
         ),
     ],
+    dependencies: [
+        .package(url: "https://github.com/DnV1eX/EnumOptionSet.git", .upToNextMajor(from: "2.0.0")),
+        .package(url: "https://github.com/gohanlon/swift-memberwise-init-macro.git", .upToNextMajor(from: "0.5.1")),
+    ],
     targets: [
         // Targets are the basic building blocks of a package, defining a module or a test suite.
         // Targets can depend on other targets in this package and products from dependencies.
         .target(
-            name: "FifthEdition"
+            name: "FifthEdition",
+            dependencies: [
+                "EnumOptionSet",
+                .product(name: "MemberwiseInit", package: "swift-memberwise-init-macro"),
+            ],
         ),
         .testTarget(
             name: "FifthEditionTests",