Add a 2nd US region in AWS such as us-west-2

There was an incident yesterday that involved DNS and affected us-east-1. We were unable to run jobs reliably throughout the day and spent the day manually retrying failed jobs. The only alternative is eu-central-1, but that has far higher latency. It would be good to have a 2nd US region available in AWS as a redundancy against an issue like this that preserves relatively low latency for US-based workflows.