added a slice operator

NoRM.Tests/CollectionUpdateTests/UpdateTests.cs

@@ -8,7 +8,7 @@ namespace Norm.Tests
 {
     public class UpdateTests : IDisposable
     {
-        private readonly Mongo _server;
+        private readonly IMongo _server;
         private readonly IMongoCollection<CheeseClubContact> _collection;
         public UpdateTests()
         {

NoRM/Commands/Qualifiers/Q.cs

@@ -47,6 +47,25 @@ public static Expando And(this QualifierCommand baseCommand, params QualifierCom
             return retval;
         }
 
+        /// <summary>
+        /// Produces a single element $slice at the specific index.
+        /// </summary>
+        /// <param name="index">The single index that the slice will be used with.</param>
+        public static SliceQualifier Slice(int index)
+        {
+            return new SliceQualifier(index);
+        }
+
+        /// <summary>
+        /// Produces a $slice qualifier at starting at the left index and going to the right index.
+        /// </summary>
+        /// <param name="left">The first index for the slice.</param>
+        /// <param name="right">The second index for the slice.</param>
+        public static SliceQualifier Slice(int left,int right)
+        {
+            return new SliceQualifier(left,right);
+        }
+
         /// <summary>
         /// construct a $where qualifier
         /// </summary>

NoRM/Commands/Qualifiers/SliceQualifier.cs

@@ -0,0 +1,26 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using Norm.BSON;
+
+namespace Norm.Commands.Qualifiers
+{
+    /// <summary>
+    /// A command that can be used as request.
+    /// </summary>
+    public class SliceQualifier : QualifierCommand
+    {
+        public SliceQualifier(int index)
+            : this(index, index)
+        {
+
+        }
+
+        public SliceQualifier(int left, int right)
+            : base("$slice", new int[] { left, right })
+        {
+
+        }
+    }
+}

NoRM/NoRM.csproj

@@ -134,6 +134,7 @@
     <Compile Include="Commands\Qualifiers\NotInQualifier.cs" />
     <Compile Include="Commands\Qualifiers\SizeQualifier.cs" />
     <Compile Include="BSON\Expando.cs" />
+    <Compile Include="Commands\Qualifiers\SliceQualifier.cs" />
     <Compile Include="Commands\Qualifiers\WhereQualifier.cs" />
     <Compile Include="Configuration\ConfigurationContainer.cs" />
     <Compile Include="Configuration\IConfigurationContainer.cs" />