Added the missing obsolete GetAll(string,string) method to IObservableOrganizationMembersClient, fixed 2 small typos in the comments

Octokit.Reactive/Clients/ObservableOrganizationMembersClient.cs

@@ -77,6 +77,21 @@ namespace Octokit.Reactive
             return _connection.GetAndFlattenAllPages<User>(ApiUrls.Members(org, filter));
         }
 
+        /// <summary>
+        /// Obsolete, <see cref="GetAll(string,OrganizationMembersFilter)"/>
+        /// </summary>
+        /// <param name="org">The login for the organization</param>
+        /// <param name="filter">The user filter</param>
+        /// <returns>The users</returns>
+        [Obsolete("No longer supported, use GetAll(string, OrganizationMembersFilter) instead")]
+        public IObservable<User> GetAll(string org, string filter)
+        {
+            Ensure.ArgumentNotNullOrEmptyString(org, "org");
+            Ensure.ArgumentNotNullOrEmptyString(filter, "filter");
+
+            return _connection.GetAndFlattenAllPages<User>(ApiUrls.Members(org, filter));
+        }
+
         /// <summary>
         /// List all users who have publicized their membership of the organization.
         /// </summary>