Handle reports that don't have a reprcrash

[punya]

Closes #713 (which happens because ReprFailDoctest doesn't have a reprcrash)

[nicoddemus]

Thanks for PR! 😄

Some requests:

• Can you also add a test for this fix? Take a look at testing/test_doctest.py for examples, seems simple to create a test for the issue;
• Add yourself to CONTRIBUTORS;
• Add a note about this in the CHANGELOG;

If by any chance you don't have the time to work on this, please let me know.

[punya]

I don't see a CONTRIBUTORS file - could you point me to the right location?

[nicoddemus]

Sorry, I meant AUTHORS. 😅

[punya]

@nicoddemus, it looks like the AppVeyor build is stuck. Thoughts on how to proceed?

[nicoddemus]

Actually it didn't even start yet, but I just tested your patch on Windows and it is OK, so I'm merging it.

Thanks again for the PR!

[punya]

When can I expect to see a release containing this change? Should I backport it to the 2.7 branch?

[nicoddemus]

I'm don't know about a release date yet. I will backport it to the 2.7 branch myself, thanks.

[punya]

Thanks for explaining, and for your quick turnaround on the PR :)

[nicoddemus]

Thanks again for the PR, Cheers! 🍻