fix(tests): report curl output if it wasn't "Powered by Deis"

If the smoke test fails, it now reports what curl does see to the
test runner for help in debugging failures.

The smoke test now registers with the router rather than directly
to the controller at port 8000, and the .HostName config field was
more appropriately named to .Domain.
Merge pull request #1442 from deis/1417-fix-smoketest-output

fix(tests): report curl output if it wasn't "Powered by Deis"