fallback on defaults

Hi Burt and Ted,

  This is one fix for the errors reported during the travis tests. We might want to wrap this `try...except` in a function that is defined once, and then called as `conf = supy.getConfiguration()`?

Davide

P.S. alternatively, we could move the testing to the `minimal-example` repo, where `configuration` is defined. However, I believe it makes sense to keep the two things separated (we could have two tests, one to check the supy internal consistency, and one for the minimal-example)...need to think more about this.