Investors interested in buying Energy Transfer might want to do it soon.It's important to take the long-term view when investing. You should think in terms of years and decades, not months and days. However, it's also wise to keep an eye on the calendar before investing to get ahead of a potential catalyst. Those interested in buying midstream giant Energy Transfer (ET -0.30%) should circle Nov. 6 on their calendar. It's an important date for the master limited partnership (MLP) because it precedes the comp ...