docs(install) remove deprecated AWS CF templates
docs(install) remove deprecated AWS CF templates

Datastax no longer supports Combo AMI for provisioning a cluster-aware Cassandra
instance, so the templates provisioning new Cassandra cluster using Cassandra
AMI have been removed.

https://github.com/riptano/ComboAMI

Signed-off-by: Thibault Charbonnier <3c2e9133e272cb489e2fea0c4328cf56b08e4226@me.com>

Mashape/getkong.org,Mashape/getkong.org,Mashape/getkong.org