Add feature request template (mshr-h#464)

Author: DeflateAwning

.github/ISSUE_TEMPLATE/feature_request.md

@@ -0,0 +1,40 @@
+---
+name: Feature request
+about: Suggest an idea for this project
+title: 'Please replace with a clear and descriptive title'
+labels: 'type: feature'
+assignees: ''
+---
+
+<!--
+Thanks for suggesting a new feature!
+
+Please fill in the sections below.
+-->
+
+**Which problem is this feature request solving?**
+
+<!--
+Example: I'm always frustrated when [...]
+-->
+
+**Describe the solution you'd like**
+
+<!--
+Example: This could be fixed by [...]
+-->
+
+**Describe alternatives you've considered**
+
+<!--
+Example: Another solution would be [...]
+-->
+
+**Can you submit a pull request?**
+
+Yes/No.
+
+<!--
+Pull requests are welcome! If you would like to help us add this feature, please check our
+[contributions guidelines](../blob/main/CONTRIBUTING.md).
+-->