Expose affiliation parameter when listing collaborators (#2043)

Octokit/Models/Request/RepositoryCollaboratorListRequest.cs

@@ -0,0 +1,57 @@
+using System.Diagnostics;
+using System.Globalization;
+using Octokit.Internal;
+
+namespace Octokit
+{
+    /// <summary>
+    /// Used to request and filter a list of repository collaborators
+    /// </summary>
+    [DebuggerDisplay("{DebuggerDisplay,nq}")]
+    public class RepositoryCollaboratorListRequest : RequestParameters
+    {
+        /// <summary>
+        /// Initializes a new instance of the <see cref="RepositoryCollaboratorListRequest" /> class.
+        /// </summary>
+        public RepositoryCollaboratorListRequest()
+        {
+            Affiliation = CollaboratorAffiliation.All; // Default in accordance with the documentation
+        }
+        
+        /// <summary>
+        /// Gets or sets the collaborator affiliation property.
+        /// </summary>
+        /// <value>
+        /// The collaborator affiliation
+        /// </value>
+        public CollaboratorAffiliation Affiliation { get; set; }
+
+        internal string DebuggerDisplay
+        {
+            get { return string.Format(CultureInfo.InvariantCulture, "Affiliation: {0}", Affiliation); }
+        }
+    }
+
+    /// <summary>
+    /// The collaborator affiliation
+    /// </summary>
+    public enum CollaboratorAffiliation
+    {
+        /// <summary>
+        /// All collaborators the authenticated user can see.
+        /// </summary>
+        [Parameter(Value = "all")]
+        All,
+        /// <summary>
+        /// All collaborators with permissions to an organization-owned repository,
+        /// regardless of organization membership status.
+        /// </summary>
+        [Parameter(Value = "direct")]
+        Direct,
+        /// <summary>
+        /// All outside collaborators of an organization-owned repository.
+        /// </summary>
+        [Parameter(Value = "outside")]
+        Outside
+    }
+}