upgrading yarn version on master

Author: Ray Manpreet  Singh Matharu <rmatharu@rmatharu-ld1.linkedin.biz>

Reviewers: Prateek Maheshwari <pmaheshwari@apache.org>

Closes #61 from rmatharu/master-scala-fix
diff --git a/bin/grid b/bin/grid
index 8b13d7a..f937e53 100755
--- a/bin/grid
+++ b/bin/grid
@@ -36,7 +36,7 @@
 SYSTEM=$2
 
 DOWNLOAD_KAFKA=https://archive.apache.org/dist/kafka/2.1.1/kafka_2.11-2.1.1.tgz
-DOWNLOAD_YARN=https://archive.apache.org/dist/hadoop/common/hadoop-2.6.1/hadoop-2.6.1.tar.gz
+DOWNLOAD_YARN=https://archive.apache.org/dist/hadoop/common/hadoop-2.7.1/hadoop-2.7.1.tar.gz
 DOWNLOAD_ZOOKEEPER=https://archive.apache.org/dist/zookeeper/zookeeper-3.4.14/zookeeper-3.4.14.tar.gz
 
 SERVICE_WAIT_TIMEOUT_SEC=20
@@ -102,7 +102,7 @@
 
 install_yarn() {
   mkdir -p "$DEPLOY_ROOT_DIR"
-  install yarn $DOWNLOAD_YARN hadoop-2.6.1
+  install yarn $DOWNLOAD_YARN hadoop-2.7.1
   cp "$BASE_DIR/conf/yarn-site.xml" "$DEPLOY_ROOT_DIR/yarn/etc/hadoop/yarn-site.xml"
   if [ ! -f "$HOME/.samza/conf/yarn-site.xml" ]; then
     mkdir -p "$HOME/.samza/conf"