[github] update issue templates (#2920)

.github/ISSUE_TEMPLATE.md

@@ -1,7 +1,3 @@
-GitHub Issues are for bugs and feature requests.  To make bugs and feature requests more easy to find and organize, we close issues that are deemed out of scope for GitHub Issues.
+GitHub Issues are for bugs and feature requests. To make bugs and feature requests more easy to find and organize, we close issues that are deemed out of scope for GitHub Issues.
 
-Usage questions? Post questions to [Stack Overflow](http://stackoverflow.com/) using the [[openthread] tag](http://stackoverflow.com/questions/tagged/openthread). We also use Google Groups for discussion and announcements:
-
-* [openthread-announce](https://groups.google.com/forum/#!forum/openthread-announce) - subscribe for release notes and new updates on OpenThread
-* [openthread-users](https://groups.google.com/forum/#!forum/openthread-users) - the best place for users to discuss OpenThread and interact with the OpenThread team
-* [openthread-devel](https://groups.google.com/forum/#!forum/openthread-devel) - team members discuss the on-going development of OpenThread
+The openthread-users Google Group is the recommended place for users to discuss OpenThread and interact directly with the OpenThread community. https://groups.google.com/forum/#!forum/openthread-users

.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**
+Information to reproduce the behavior, including:
+1. Git commit id
+2. IEEE 802.15.4 hardware platform
+3. Build steps
+4. Network topology
+
+**Expected behavior**
+A clear and concise description of what you expected to happen.
+
+**Console/log output**
+If applicable, add console/log output to help explain your problem.
+
+**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.
+
+**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.