Fix out-of-scope variable from commit 4e5ec539
Show exception class for API errors
Propagate errots/status to 'td' entry point
Support idcfcloud.com domains

Changes:
* relax string based validation of the domain by limiting
  validation on the IP address alone
* verify the IP endpoint is valid by checking the status
  endpoint /v3/system/server_status
* NOTE: if the -e option is used, a call to the health
  check api will happen at every command...

Fixes CLT-396