merging in master changes

conf/slaves

-ec2-23-20-12-62.compute-1.amazonaws.com
-ec2-54-205-173-19.compute-1.amazonaws.com
-ec2-54-225-4-124.compute-1.amazonaws.com
-ec2-23-22-209-112.compute-1.amazonaws.com
-ec2-50-16-69-88.compute-1.amazonaws.com
-ec2-54-205-163-126.compute-1.amazonaws.com
-ec2-54-242-235-95.compute-1.amazonaws.com
-ec2-54-211-169-232.compute-1.amazonaws.com
-ec2-54-237-31-30.compute-1.amazonaws.com
-ec2-54-235-15-124.compute-1.amazonaws.com
+# A Spark Worker will be started on each of the machines listed below.
+localhost
\ No newline at end of file

conf/spark-env.sh.template

 #!/usr/bin/env bash
 
 # This file contains environment variables required to run Spark. Copy it as
-# spark-env.sh and edit that to configure Spark for your site. At a minimum,
-# the following two variables should be set:
-# - SCALA_HOME, to point to your Scala installation, or SCALA_LIBRARY_PATH to
-#   point to the directory for Scala library JARs (if you install Scala as a
-#   Debian or RPM package, these are in a separate path, often /usr/share/java)
+# spark-env.sh and edit that to configure Spark for your site.
+#
+# The following variables can be set in this file:
+# - SPARK_LOCAL_IP, to set the IP address Spark binds to on this node
 # - MESOS_NATIVE_LIBRARY, to point to your libmesos.so if you use Mesos
+# - SPARK_JAVA_OPTS, to set node-specific JVM options for Spark. Note that
+#   we recommend setting app-wide options in the application's driver program.
+#     Examples of node-specific options : -Dspark.local.dir, GC options
+#     Examples of app-wide options : -Dspark.serializer
 #
-# If using the standalone deploy mode, you can also set variables for it:
-# - SPARK_MASTER_IP, to bind the master to a different IP address
+# If using the standalone deploy mode, you can also set variables for it here:
+# - SPARK_MASTER_IP, to bind the master to a different IP address or hostname
 # - SPARK_MASTER_PORT / SPARK_MASTER_WEBUI_PORT, to use non-default ports
 # - SPARK_WORKER_CORES, to set the number of cores to use on this machine
 # - SPARK_WORKER_MEMORY, to set how much memory to use (e.g. 1000m, 2g)
 # - SPARK_WORKER_PORT / SPARK_WORKER_WEBUI_PORT
-# - SPARK_WORKER_INSTANCES, to set the number of worker instances/processes
-#   to be spawned on every slave machine
+# - SPARK_WORKER_INSTANCES, to set the number of worker processes per node