[SPARK-12805][MESOS] Fixes documentation on Mesos run modes
[SPARK-12805][MESOS] Fixes documentation on Mesos run modes

The default run has changed, but the documentation didn't fully reflect the change.

Author: Luc Bourlier <luc.bourlier@typesafe.com>

Closes #10740 from skyluc/issue/mesos-modes-doc.

(cherry picked from commit cc91e21879e031bcd05316eabb856e67a51b191d)
Signed-off-by: Reynold Xin <c9d35a384bc579d1c6c8c055f2a2b5c04e11b521@databricks.com>

haowu80s/spark,haowu80s/spark,haowu80s/spark,haowu80s/spark,haowu80s/spark,haowu80s/spark