remove stale MaxElapsedTime comments

Author: cenkalti

exponential.go

@@ -28,13 +28,7 @@ multiplied by the exponential, that is, between 2 and 6 seconds.
 
 Note: MaxInterval caps the RetryInterval and not the randomized interval.
 
-If the time elapsed since an ExponentialBackOff instance is created goes past the
-MaxElapsedTime, then the method NextBackOff() starts returning backoff.Stop.
-
-The elapsed time can be reset by calling Reset().
-
-Example: Given the following default arguments, for 10 tries the sequence will be,
-and assuming we go over the MaxElapsedTime on the 10th try:
+Example: Given the following default arguments, for 9 tries the sequence will be:
 
 	Request #  RetryInterval (seconds)  Randomized Interval (seconds)
 
@@ -47,7 +41,6 @@ and assuming we go over the MaxElapsedTime on the 10th try:
 	 7          5.692                   [2.846,  8.538]
 	 8          8.538                   [4.269, 12.807]
 	 9         12.807                   [6.403, 19.210]
-	10         19.210                   backoff.Stop
 
 Note: Implementation is not thread-safe.
 */