Run default addressables build conditionally (#231)

* Add asmdef and Addressable content build in the builder

* Move asmdef content into its own directory

* Mark UnityBuilderAction as Editor-only

dist/default-build-script/Assets/Editor/UnityBuilderAction/Versioning/VersionApplicator.cs

@@ -0,0 +1,27 @@
+using System;
+using UnityEditor;
+
+namespace UnityBuilderAction.Versioning
+{
+  public class VersionApplicator
+  {
+    public static void SetVersion(string version)
+    {
+      if (version == "none") {
+        return;
+      }
+
+      Apply(version);
+    }
+
+    public static void SetAndroidVersionCode(string androidVersionCode) {
+      PlayerSettings.Android.bundleVersionCode = Int32.Parse(androidVersionCode);
+    }
+
+    static void Apply(string version)
+    {
+      PlayerSettings.bundleVersion = version;
+      PlayerSettings.macOS.buildNumber = version;
+    }
+  }
+}