fix(controller): remove application logs on delete
fix(controller): chown log mount to deis user

This will grant the controller read/write permissions for the logs.
test(integration): add tests for `deis limits` commands
docs(*): clarify that auth SSH key for clusters cannot have a password
Merge pull request #1569 from deis/1542-test-deis-limits

test(integration): add tests for `deis limits` commands
Merge pull request #1580 from deis/clarify_auth_key

docs(*): clarify that auth SSH key for clusters cannot have a password
Merge pull request #1521 from deis/1354-delete-logs

fix(controller): remove application logs on delete