fix(verification): pass validation error message on

[thombergs]

Verification error message is now passed on instead of being swallowed.

I'm not sure if it has any side effects, but at least for my use case (through karma-pact) this change made the experience of writing consumer tests much more pleasant, since I can now see what went wrong in the karma results in the browser.

fixes #113

[coveralls]

Coverage remained the same at 95.767% when pulling ca0b052 on thombergs:errorhandling into f5387a0 on pact-foundation:master.

[mefellows]

It makes sense. Could you please elaborate as to why the stack trace should be removed? It's typical of a test framework to output the results to a terminal, but I suspect perhaps this is less helpful in the Karma-like use cases?

[coveralls]

Coverage remained the same at 95.767% when pulling a381198 on thombergs:errorhandling into f5387a0 on pact-foundation:master.

[coveralls]

Coverage remained the same at 95.767% when pulling 3041282 on thombergs:errorhandling into 6d2ad81 on pact-foundation:master.

[thombergs]

Took a couple commits to fix the test, because I couldn't get them to run on Windows (might make a separate PR for that), so I force pushed a clean history. The CI build still fails however, but because of some other reason.

I removed the error log since I assumed whatever framework is calling the verify() function will output the error as it sees fit and I don't see why it should be logged twice.

I'm not very deep into the JS ecosystem, however, so I don't really know the best practice here :).

[mefellows]

Thanks. Not sure what is going on with the Node 4.x.x build but it's related to the karma examples I updated in master last night, not your change which is good to bring in.

Let's see how this goes!