Run phan self-test as part of the jenkins gauntlet
Run phan self-test as part of the jenkins gauntlet

./phan should output nothing with its own ./phan/config.php, and have a
non-zero exit code.

- Note that the default behavior of phan is to have a non-zero exit code
  if there are one or more errors, so no more steps are needed.

etsy/phan,ArtemGordinsky/phan,ArtemGordinsky/phan,etsy/phan