babushka: test-driven sysadmin

The idea is this: you take a job that you'd rather not do manually, and describe it to babushka using its DSL. The way it works, babushka not only knows how to accomplish each part of the job, it also knows how to check if each part is already done. You're teaching babushka to achieve an end goal with whatever runtime conditions you throw at it, not just to perform the task that would get you there from the very start.