Adding template for opening new issue

[markkuleinio]

I'd suggest adding an issue template here in the GitHub. Nothing too fancy, maybe requesting basic information (versions etc) and if the issue is about a real issue or a feature request, and a sample code request as well. I think it would save time for both issue submitters and developers.

Now that NetBox has removed the reference to Google Groups, maybe enabling GitHub Discussions is an additional option for pynetbox as well. It is evident that there will be instructional requests as well anyway.