Print exception contents when test fails due to exception

[jorsanpe]

I've found that when a test fails because of an exception, the information provided is quite limited. It would be nice to print the exception contents. For example, when using fakeit, a verification failure results in an exception than contains the information about the failed verification. If this information is not printed, it's quite hard to trace why the exception happened or even if it was related to fakeit at all.