Update README for sequential load strategy

README.md

@@ -32,5 +32,6 @@ There are a couple built-in strategies for generating load, or you can implement
 * `ConstantUserLoadStrategy`: Attempts to maintain a constant concurrent user load at each given check interval until the given duration has passed.
 * `OneShotBurstLoadStrategy`: Enqueue the given number of tasks all at once. Does not repeat.
 * `RepeatBurstLoadStrategy`: Repeat enqueueing the given count of tasks at each given interval until the given duration has passed.
+* `SequentialLoadStrategy`: An aggregate strategy that executes multiple load strategies in order. Great for creating scenarios like step up, then hold steady, then step down.
 * `SteppedBurstLoadStrategy`: Enqueue an increasing (or decreasing) burst of tasks in a stepwise manner, regardless of how many are still running.
 * `SteppedUserLoadStrategy`: Attempts to maintain an increasing (or decreasing) concurrent user load in a stepwise manner.