make check should generate error on missing dependencies

[likewise]

As an enhancement, for build systems it would be good if "make check" would return with an error code if any dependency is missing.

[krogueintel]

I have a lot on my plate now in terms of getting a release of 1.0. I am happy to accept a pull request implementing this though.

[likewise]

I will have a look at it. Otherwise this issue is just a reminder to self.