create GroupList object.

#30

DataCenter_Windows/WindowsDataCenter/Interfaces/GroupList.cs

@@ -0,0 +1,17 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+
+namespace Interfaces
+{
+    public class GroupList
+    {
+        public GroupList()
+        {
+            Groups = new List<Group>();
+        }
+        public List<Group> Groups { get; set; }
+    }
+}

DataCenter_Windows/WindowsDataCenter/Interfaces/Interfaces.csproj

@@ -43,6 +43,7 @@
     <Compile Include="AppDetails.cs" />
     <Compile Include="DailyLogs.cs" />
     <Compile Include="Group.cs" />
+    <Compile Include="GroupList.cs" />
     <Compile Include="ILogger.cs" />
     <Compile Include="IRepository.cs" />
     <Compile Include="Identifier.cs" />