Redundancy for Puma app server

[cshinaver]

Implemented with nginx redirect to secondary puma process. Does not handle case of nginx failure or full node failure.

• [x] Create a secondary master node on AWS #34
• [x] Provision secondary master node to run Puma server
• [ ] Connect secondary master to primary master's database (Requires #1 to be completed)
• [ ] Update nginx configuration to use secondary master if primary master fails
• [ ] Test and verify redundancy of failure of primary master

[cshinaver]

https://www.digitalocean.com/community/tutorials/how-to-scale-ruby-on-rails-applications-across-multiple-droplets-part-1

[cshinaver]

^ Essentially just add extra app servers into nginx config