Update RecoverableNetworkWordCount.scala

Trying this example, I missed the moment when the checkpoint was iniciated

Author: comcmipi <pitonak@fns.uniba.sk>

Closes #2735 from comcmipi/patch-1 and squashes the following commits:

b6d8001 [comcmipi] Update RecoverableNetworkWordCount.scala
96fe274 [comcmipi] Update RecoverableNetworkWordCount.scala
[SPARK-4312] bash doesn't have "die"

sbt-launch-lib.bash includes `die` command but it's not valid command for Linux, MacOS X or Windows.

Closes #2898

Author: Jey Kottalam <jey@kottalam.net>

Closes #3182 from sarutak/SPARK-4312 and squashes the following commits:

24c6677 [Jey Kottalam] bash doesn't have "die"
SPARK-4230. Doc for spark.default.parallelism is incorrect

Author: Sandy Ryza <sandy@cloudera.com>

Closes #3107 from sryza/sandy-spark-4230 and squashes the following commits:

37a1d19 [Sandy Ryza] Clear up a couple things
34d53de [Sandy Ryza] SPARK-4230. Doc for spark.default.parallelism is incorrect