Create bug-report.md (#762)

.github/ISSUE_TEMPLATE/bug-report.md

+---
+name: Create an issue
+about: Report an issue or question while using nni instance (deployment).
+
+
+---
+
+<!-- Please use this template while reporting an issue and provide as much info as possible. Not doing so may result in your bug not being addressed in a timely manner. Thanks!-->
+
+
+**Short summary about the issue/question**:
+
+**Brief what process you are following**: 
+
+<!--deployment related issues
+Please fill this for deployment related issues: 
+- Operating type: Initial deployment / upgrading / operating etc.
+- Brief what deployment process you are following -->
+
+**How to reproduce it**: 
+
+<!--Fill the following information if your issue need diagnostic support from the team, as minimally and precisely as possible!-->
+
+**nni Environment**:
+- nni version:
+- nni mode(local|pai|remote):
+- OS:
+- python version:
+- is conda or virtualenv used?: 
+- is running in docker?:
+
+**Anything else we need to know**: