Clone from heroku/api, but keep calling the directory core.
Version bump.
Merge pull request #21 from heroku/fix-core-db-task

Fix core db task

When the repo was changed to heroku/api, it also implicitly changed the name of the directory that it's cloned into to api, not core. This breaks the task. I've just added an extra argument to the clone command to keep calling the directory core.