Add interface and required entities for Commit Comments.

Octokit/Models/Request/NewCommitComment.cs

@@ -0,0 +1,43 @@
+using System;
+using System.Diagnostics;
+using System.Globalization;
+
+namespace Octokit
+{
+    /// <summary>
+    /// Describes a new commit comment to create via the <see cref="IRepositoryCommentsClient.Create(string,string,string,NewCommitComment)"/> method.
+    /// </summary>
+    [DebuggerDisplay("{DebuggerDisplay,nq}")]
+    public class NewCommitComment
+    {
+        public NewCommitComment(string body)
+        {
+            Ensure.ArgumentNotNull(body, "body");
+
+            Body = body;
+        }
+
+        /// <summary>
+        /// The contents of the comment (required)
+        /// </summary>
+        public string Body { get; private set; }
+
+        /// <summary>
+        /// Relative path of the file to comment on
+        /// </summary>
+        public string Path { get; set; }
+
+        /// <summary>
+        /// Line index in the diff to comment on
+        /// </summary>
+        public int? Position { get; set; }
+
+        internal string DebuggerDisplay
+        {
+            get
+            {
+                return String.Format(CultureInfo.InvariantCulture, "Path: {0}, Body: {1}", Path, Body);
+            }
+        }
+    }
+}