added Safe.DispatchEvent() a legacy equivalent for '?.Invoke()' added Safe.Dispose(IEnumerable) added PromiseExtensions.CancellationPoint to add a cancellation point to the chain of promises added IPromise<T> PromiseExtensions.Then<T>(this IPromise<T> that, Action<T> success) overloads added PromiseExtensions.Error() overloads to handle a error or(and) a cancellation

using System;

namespace Implab {
    public interface ICancellable {
        void Cancel();
        void Cancel(Exception reason);
    }
}