Makefile

* add scripts to run migrations and check the status of all migrations
  both locally and on prod
* group all ansible playbook scripts under an `ansible.` make command prefix
* move the swap memory tasks to the end of the `provision.yml`
  playbook since they sometimes fail on some hosting providers (b/c
  osvz conflicts or something) and we don't want that to prevent the
  rest of the playbook from running
* clean up docker scripts to use `exec` that were using `run` unnecessarily