add support for named site options

Oqtane.Server/Infrastructure/Options/SiteNamedOptions.cs

@@ -0,0 +1,28 @@
+using System;
+using System.Collections.Generic;
+using Oqtane.Models;
+
+namespace Oqtane.Infrastructure
+{
+    public class SiteNamedOptions<TOptions> : ISiteNamedOptions<TOptions>
+        where TOptions : class, new()
+    {
+        public string Name { get; }
+
+        private readonly Action<TOptions, Alias, Dictionary<string, string>> configureOptions;
+
+        public SiteNamedOptions(string name, Action<TOptions, Alias, Dictionary<string, string>> configureOptions)
+        {
+            Name = name;
+            this.configureOptions = configureOptions;
+        }
+
+        public void Configure(string name, TOptions options, Alias alias, Dictionary<string, string> sitesettings)
+        {
+            if (name == Name)
+            {
+                configureOptions(options, alias, sitesettings);
+            }
+        }
+    }
+}