add theme creator module to simplify the scaffolding of external themes

Oqtane.Server/wwwroot/Themes/Templates/External/Client/ThemeInfo.cs

@@ -0,0 +1,15 @@
+using Oqtane.Models;
+using Oqtane.Themes;
+
+namespace [Owner].[Theme]
+{
+    public class ThemeInfo : ITheme
+    {
+        public Theme Theme => new Theme
+        {
+            Name = "[Theme]",
+            Version = "1.0.0"
+        };
+
+    }
+}