chore(): add issue template

Author: jelbourn

.github/ISSUE_TEMPLATE.md

@@ -0,0 +1,33 @@
+**Note: for support questions, please use one of these channels:**
+https://github.com/angular/material2/blob/master/CONTRIBUTING.md#question.
+This repository's issues are reserved for feature requests and bug reports.
+
+* **Do you want to request a *feature* or report a *bug*?**
+
+
+
+* **What is the current behavior?**
+
+
+
+* **If the current behavior is a bug,
+please provide steps to reproduce and if possible a minimal demo of the problem**
+via https://plnkr.co or similar.
+
+
+* **What is the expected behavior?**
+
+
+
+* **What is the motivation / use case for changing the behavior?**
+
+
+
+* **Which version of Angular and Material, and which browser and OS does this issue affect?**
+Did this work in previous versions of Angular / Material?
+Please also test with the latest stable and snapshot versions.
+
+
+
+* **Other information**
+(e.g. detailed explanation, stacktraces, related issues, suggestions how to fix)