Add kerberos package for centos 7 installation

continuousintegration/buildtree_runner/vmBootstrap/bootstrapSystem.sh

@@ -15,7 +15,7 @@ cat gitScripts/bash_profile.hook >> ~eric/.bash_profile
 sudo -u eric cp tigConf/tigrc ~eric/.tigrc
 
 echo Installing minimal tools and tape tools
-yum install -y git cmake rpm-build gcc gcc-c++ vim gdb cgdb strace ltrace screen tig lsscsi mt-st mtx sg3_utils jq psmisc mariadb-devel yum-plugin-versionlock
+yum install -y git cmake rpm-build gcc gcc-c++ vim gdb cgdb strace ltrace screen tig lsscsi mt-st mtx sg3_utils jq psmisc mariadb-devel yum-plugin-versionlock krb5-workstation
 
 (cd / ; sudo -u eric git config --global color.ui true)
 (cd / ; sudo -u eric git config --global user.email "Eric.Cano@cern.ch")