Add strict budget controls

[zanerock]

Overview

One of the huge and persistent downsides of AWS is lack of strict budget management. You can set budgets and get warnings, but that's about it. There's no built-in way to tell AWS "don't charge me for more than X".

We can fix this, though. Using the cost services and tying the budget alert to logic, we can start to throttle the website as budget limits are approached.