Invalid HCL in configuration file manifests as "missing API token"

[nphilbrook]

Is your feature request related to a problem? Please describe.
When I foolishly pass in an invalid HCL file to TFM, the error reported is

Error creating client on attempt 1: missing API token

With a lot of retrying

Describe the solution you'd like
An error message describing the failure to parse the HCL file and a fast fail.

Describe alternatives you've considered
n/a

Additional context
A --verbose option as described in #61 would probably help this failure mode be less mysterious, but I think it still makes sense on its own.