Add an ISSUE_TEMPLATE

[fkaelberer]

Github recently introduced issue templates that help contributors to provide necessary information.
I think this should reduce the number of information requests. What do you think about such a template?

https://github.com/blog/2111-issue-and-pull-request-templates

Edit: Try the template at https://github.com/fkaelberer/pdf.js/issues/new, resulting issues look like fkaelberer#4.

[Snuffleupagus]

Perhaps it would be a good idea to also indicate that GitHub now supports attaching PDF files to issues?

[Snuffleupagus]

I think this is a great idea!
Besides my comment above, would it make sense to also add a link to https://github.com/mozilla/pdf.js/blob/master/CONTRIBUTING.md at the top of the template (e.g. "Please also read CONTRIBUTING.md", or something like that)?

[yurydelendik]

"Please also read CONTRIBUTING.md"

We can keep this out. However I would move both ISSUE_TEMPLATE.md and CONTRIBUTING.md into .github/ folder (as post suggested)

[yurydelendik]

I was thinking about something less busy (similar to what chromium project had), e.g.:

Link to PDF file (or attach file here):

Configuration:
- Web browser and its version:
- Operating system and its version:
- PDF.js version:
- Is an extension:

Steps to reproduce the problem:
1. 
2.

What is the expected behavior? (add screenshot)

What went wrong? (add screenshot)

Link to a viewer (if hosted on a site other than mozilla.github.io/pdf.js or as Firefox/Chrome extension):

P.S. modified

[timvandermeij]

I definitely think we should add this. I like @yurydelendik's suggestion as it's more compact, yet still contains all required information.

[fkaelberer]

Thanks for your feedback. @yurydelendik, I used your text.

[timvandermeij]

Looks good, thank you! I'm confident that this will lead to better issue descriptions.