ISSUE_TEMPLATE.md

How to reproduce

• Leaflet version I'm using:
• Browser (with version) I'm using:
• OS/Platform (with version) I'm using:
• step 1
• step 2

What behaviour I'm expecting and which behaviour I'm seeing

Minimal example reproducing the issue

• this example is as simple as possible
• this example does not rely on any third party code

Using http://leafletjs.com/edit.html or any other jsfiddle-like site.