Use valid box name for ubuntu14.04
Use valid box name for ubuntu14.04

wywygmbh/puppet-cassandra,sigmunau/puppet-cassandra,3fs/puppet-cassandra,msimonin/puppet-cassandra,3fs/puppet-cassandra,igoraj/puppet-cassandra,wywygmbh/puppet-cassandra,3fs/puppet-cassandra,igoraj/puppet-cassandra,igoraj/puppet-cassandra,msimonin/puppet-cassandra,sigmunau/puppet-cassandra,wywygmbh/puppet-cassandra,sigmunau/puppet-cassandra