Zookeeper 3.4.6 seems no longer existent on http://apache.osuosl.org

Move to using 3.4.7 which is on http://apache.osuosl.org

Fixes issue #375

Author: harlowja

ensure-zookeeper-env.sh

@@ -4,7 +4,7 @@ set -e
 
 HERE=`pwd`
 ZOO_BASE_DIR="$HERE/zookeeper"
-ZOOKEEPER_VERSION=${ZOOKEEPER_VERSION:-3.4.6}
+ZOOKEEPER_VERSION=${ZOOKEEPER_VERSION:-3.4.7}
 ZOOKEEPER_PATH="$ZOO_BASE_DIR/$ZOOKEEPER_VERSION"
 ZOO_MIRROR_URL="http://apache.osuosl.org/"