SPARK-2231: dev/run-tests should include YARN and use a recent Hadoop version

...rsion

Author: Patrick Wendell <pwendell@gmail.com>

Closes #1175 from pwendell/test-hadoop-version and squashes the following commits:

9210ef4 [Patrick Wendell] SPARK-2231: dev/run-tests should include YARN and use a recent Hadoop version

dev/run-tests

@@ -21,6 +21,9 @@
 FWDIR="$(cd `dirname $0`/..; pwd)"
 cd $FWDIR
 
+export SPARK_HADOOP_VERSION=2.3.0
+export SPARK_YARN=true
+
 # Remove work directory
 rm -rf ./work