Change Kafka Version used in bin/grid

The old tgz used in bin/grid is broken and it makes bin/grid can't install Kafka. So I changed it to a newer version to make it run properly again.

Author: Imre Nagi <imre.nagi2812@gmail.com>

Reviewers: Jagadish<jagadish@apache.org>

Closes #26 from imrenagi/master
diff --git a/bin/grid b/bin/grid
index 5dff403..f31824b 100755
--- a/bin/grid
+++ b/bin/grid
@@ -35,7 +35,7 @@
 COMMAND=$1
 SYSTEM=$2
 
-DOWNLOAD_KAFKA=http://www.us.apache.org/dist/kafka/0.10.1.1/kafka_2.11-0.10.1.1.tgz
+DOWNLOAD_KAFKA=http://www.us.apache.org/dist/kafka/0.10.2.1/kafka_2.11-0.10.2.1.tgz
 DOWNLOAD_YARN=https://archive.apache.org/dist/hadoop/common/hadoop-2.6.1/hadoop-2.6.1.tar.gz
 DOWNLOAD_ZOOKEEPER=http://archive.apache.org/dist/zookeeper/zookeeper-3.4.3/zookeeper-3.4.3.tar.gz
 
@@ -112,7 +112,7 @@
 
 install_kafka() {
   mkdir -p "$DEPLOY_ROOT_DIR"
-  install kafka $DOWNLOAD_KAFKA kafka_2.11-0.10.1.1
+  install kafka $DOWNLOAD_KAFKA kafka_2.11-0.10.2.1
   # have to use SIGTERM since nohup on appears to ignore SIGINT
   # and Kafka switched to SIGINT in KAFKA-1031.
   sed -i.bak 's/SIGINT/SIGTERM/g' $DEPLOY_ROOT_DIR/kafka/bin/kafka-server-stop.sh