Fix Cassandra element

The pip command was not installed.  Added a couple of
prerequisites (snappy, Cython) and db management package.
The cassandra-tools package provides commands for enabling
and disabling incremental backup, snapshots, and many other
features.  It is provided by the cassandra community.

Change-Id: If0f807878d6f3da17e33bc9e40ecb9563de61a25

integration/scripts/files/elements/ubuntu-cassandra/install.d/10-cassandra

@@ -15,16 +15,20 @@ export DEBIAN_FRONTEND=noninteractive
 apt-get --allow-unauthenticated install -qy curl
 echo "deb http://www.apache.org/dist/cassandra/debian ${CASSANDRA_RELEASE} main" >> /etc/apt/sources.list.d/cassandra.sources.list
 curl https://www.apache.org/dist/cassandra/KEYS | sudo apt-key add -
-apt-get update
+apt-get -y update
 apt-get --allow-unauthenticated install -qy openjdk-${CASSANDRA_JAVA}-jdk expect python-dev
-apt-get --allow-unauthenticated install -qy libxml2-dev ntp mc
+apt-get --allow-unauthenticated install -qy libxml2-dev ntp mc libev4 libev-dev
 apt-get --allow-unauthenticated install -qy libxslt1-dev python-pexpect
 apt-get --allow-unauthenticated install -qy python-migrate build-essential
+apt-get --allow-unauthenticated install -qy python-setuptools python-pip python-snappy
 
-apt-get --allow-unauthenticated install -qy cassandra
+apt-get --allow-unauthenticated install -qy cassandra cassandra-tools
+
+pip2 install Cython
 
 # The Python Driver 2.0 for Apache Cassandra.
 pip2 install cassandra-driver
+
 # Sorted sets support for the Python driver.
 pip2 install blist
 

integration/scripts/trovestack

@@ -578,7 +578,7 @@ function cmd_set_datastore() {
         VERSION="3.2.6"
     elif [ "$DATASTORE_TYPE" == "cassandra" ]; then
         PACKAGES=${PACKAGES:-"cassandra"}
-        VERSION="2.1.0"
+        VERSION="3.11.1"
     elif [ "$DATASTORE_TYPE" == "couchbase" ]; then
         PACKAGES=${PACKAGES:-"couchbase-server"}
         VERSION="2.2.0"