Travis scripts should gracefully exit for external users

[kshakir]

Currently when an external user attempts to access our cloud accounts, Travis does not hand out the encryption keys. This is desired behavior, as we do not want to run up bills on unknown code from outside users.

However, currently our test scripts are not checking the variable TRAVIS_SECURE_ENV_VARS, and are instead trying to access encrypted variables that are not and never will be present. This leads to false negatives where the tests are marked as failed, when instead they should best case be marked as ignored, worst case be marked as implicitly passed.