add support for organization web hooks (#1884)

Octokit/Clients/IOrganizationsClient.cs

@@ -24,6 +24,12 @@ namespace Octokit
         /// </summary>
         ITeamsClient Team { get; }
 
+        /// <summary>
+        /// A client for GitHub's Organization Hooks API.
+        /// </summary>
+        /// <remarks>See <a href="https://developer.github.com/v3/orgs/hooks/">Hooks API documentation</a> for more information.</remarks>
+        IOrganizationHooksClient Hook { get; }
+
         /// <summary>
         /// Returns a client to manage outside collaborators of an organization.
         /// </summary>
@@ -94,10 +100,10 @@ namespace Octokit
         /// <summary>
         /// Update the specified organization with data from <see cref="OrganizationUpdate"/>.
         /// </summary>
-        /// <param name="organizationName">The name of the organization to update.</param>
+        /// <param name="org">The name of the organization to update.</param>
         /// <param name="updateRequest"></param>
         /// <exception cref="AuthorizationException">Thrown if the client is not authenticated.</exception>
         /// <returns>A <see cref="Organization"/></returns>
-        Task<Organization> Update(string organizationName, OrganizationUpdate updateRequest);
+        Task<Organization> Update(string org, OrganizationUpdate updateRequest);
     }
 }