Add PR template

Author: Gumball2415

docs/pull_request_template.md

@@ -0,0 +1,9 @@
+This pull request aims to `(specify reason)`.
+
+(If updating documentation due to a new feature/change)
+This pull request corresponds to Dn-Programming-Core-Management/Dn-FamiTracker#`<PR number>`.
+
+### Changes in this PR:
+
+- (cite all changes made in this PR for change log)
+	- Fixes/addresses issue `#<issue number>`.