apache/incubator-spark — pull request #330 by tgravescs (2014-01-04 17:55:14+00:00)
Title: Fix handling of empty SPARK_EXAMPLES_JAR

Currently if SPARK_EXAMPLES_JAR is left unset you get a null pointer exception when running the examples (atleast on spark on yarn). The null now gets turned into a string of "null" when its put into the SparkConf so addJar no longer properly ignores it. This fixes that so that it can be left unset.