Update issue templates

Author: Zeng Tianyu

.github/ISSUE_TEMPLATE/bug_report.md

@@ -0,0 +1,24 @@
+---
+name: Bug report
+about: Create a report to help us improve
+
+---
+
+**Describe the bug**
+*A clear and concise description of what the bug is*
+
+**To Reproduce**
+*Steps to reproduce the behavior*
+
+**Expected behavior**
+*A clear and concise description of what you expected to happen*
+
+**Screenshots (Optional)**
+*If applicable, add screenshots to help explain your problem*
+
+**Desktop (please complete the following information):**
+ - Browser: *[e.g. chrome, safari]*
+ - Mac OS X  Version: *[e.g. 22]*
+
+**Additional context**
+*Add any other context about the problem here*

.github/ISSUE_TEMPLATE/feature_request.md

@@ -0,0 +1,17 @@
+---
+name: Feature request
+about: Suggest an idea for this project
+
+---
+
+**Is your feature request related to a problem? Please describe.**
+*A clear and concise description of what the problem is. Ex. I'm always frustrated when [...]*
+
+**Describe the solution you'd like**
+*A clear and concise description of what you want to happen*
+
+**Describe alternatives you've considered**
+*A clear and concise description of any alternative solutions or features you've considered*
+
+**Additional context**
+*Add any other context or screenshots about the feature request here*