new command - errands to show available errands from deployment manifest
spec for 'errands' command
fix for CI error
run errand - prompts for which errand to run if not specified
spiking out GET /errands
Spec for GET /deployments/:name/errands
bosh errands/bosh run errands uses director.list_errands
Remove VMs column

Errands don't have more than 1 instance
Clean up pull request 625

Signed-off-by: Andrea Law <alaw@pivotal.io>