add PR template

.github/PULL_REQUEST_TEMPLATE/pull_request_template.md

@@ -0,0 +1,17 @@
+## Checklist 
+
+- [ ] update NEWS.md
+- [ ] documentation updated with `devtools::document()`
+- [ ] `devtools::check()` passes locally
+
+## Changes 
+
+Describe the changes to the repository. What is being added or removed? What design choices were made that should be reviewed?
+
+**Issues that this closes** 
+
+Please link any issues that are closed by this PR
+
+## Follow up tasks
+
+Are there any follow up tasks to be addressed after this PR is merged?