Create Fastly white-list for HTTP ports 80 and 443

[preaction]

Since we are using Fastly for some of our hosts, we should white-list that only Fastly is allowed to access Apache. The list of Fastly IP blocks is https://api.fastly.com/public-ip-list. If the IP is not in this list, they should not be allowed access to domains we are hosting through Fastly.

We should add a set of Allow constraints to the Apache configuration for the following domains:

• devel.cpantesters.org
• pass.cpantesters.org
• www.cpantesters.org
• stats.cpantesters.org
• static.cpantesters.org

These constraints should be updated every day using a cron job. @ranguard says they update this only every few months or so, so a nightly rebuild should be fine.

We could use iptables to white-list, but that will only work if we serve all content through Fastly, which we currently do not.