added basic xml comments to all Oqtane.Services interfaces

Oqtane.Client/Services/Interfaces/ISiteTemplateService.cs

@@ -1,11 +1,18 @@
-using Oqtane.Models;
+using Oqtane.Models;
 using System.Collections.Generic;
 using System.Threading.Tasks;
 
 namespace Oqtane.Services
 {
+    /// <summary>
+    /// Service to retreive <see cref="SiteTemplate"/> entries
+    /// </summary>
     public interface ISiteTemplateService
     {
+        /// <summary>
+        /// Returns a list of site templates
+        /// </summary>
+        /// <returns></returns>
         Task<List<SiteTemplate>> GetSiteTemplatesAsync();
     }
 }