[SPARK-2109] Setting SPARK_MEM for bin/pyspark does not work.

Trivial fix.

Author: Prashant Sharma <prashant.s@imaginea.com>

Closes #1050 from ScrapCodes/SPARK-2109/pyspark-script-bug and squashes the following commits:

77072b9 [Prashant Sharma] Changed echos to redirect to STDERR.
13f48a0 [Prashant Sharma] [SPARK-2109] Setting SPARK_MEM for bin/pyspark does not work.
[HOTFIX] Synchronize on SQLContext.settings in tests.

Let's see if this fixes the ongoing series of test failures in a master build machine (https://amplab.cs.berkeley.edu/jenkins/job/Spark-Master-SBT-pre-YARN/SPARK_HADOOP_VERSION=1.0.4,label=centos/81/).

pwendell marmbrus

Author: Zongheng Yang <zongheng.y@gmail.com>

Closes #1277 from concretevitamin/test-fix and squashes the following commits:

28c88bd [Zongheng Yang] Synchronize on SQLContext.settings in tests.