Merge pull request #6024 from jenshnielsen/issue_template

Add Issue template with some guidelines

.github/ISSUE_TEMPLATE.md

@@ -0,0 +1,11 @@
+To help us understand and resolve your issue please check that you have provided
+the information below.
+
+- [ ] Matplotlib version, Python version and Platform (Windows, OSX, Linux ...)
+- [ ] How did you install Matplotlib and Python (pip, anaconda, from source ...)
+- [ ] If possible please supply a [Short, Self Contained, Correct, Example](http://sscce.org/)
+      that demonstrates the issue i.e a small piece of code which reproduces the issue
+      and can be run with out any other (or as few as possible) external dependencies.
+- [ ] If this is an image generation bug attach a screenshot demonstrating the issue.
+- [ ] If this is a regression (Used to work in an earlier version of Matplotlib), please 
+      note where it used to work.