upgrade Ubuntu from 12.04 to 14.04
upgrade Chef to from 11.8.2 to 11.16.0
upgrade Cassandra from 2.0.3 to 2.0.9
upgrade java from 1.7.0\_51 to 1.7.0\_67
increased RAM from 512 to 1024
switch from cassandra::tarball to cassandra::datastax
add apache2 licence
add explicit versions to Cheffile
add `ssl_verify_mode = :verify_peer` configuration to remove chef warning
update README to reflect changes