/// <summary>
/// Adds follower's as a listener when Start.
/// </summary>
/// <param name="follower"></param>
/// <remarks>To avoid recursion, followe <see cref="DetachOnStart(this Generator source, Generator)"/> the calling generator. </remarks>
public static void AttachOnBegin(this ComponentGenerator source, ComponentGenerator follower)
{
//avoid recursion
follower.DetachOnBegin(source);
source.OnBeginEventHandler += (e, a) => follower.Begin();
}
