Add PR template

Author: joshka

.github/pull_request_template.md

@@ -0,0 +1,22 @@
+<!-- Thanks for making Ratatui awesome! 🐭 -->
+
+* Link to your project (GitHub/crates.io): <!-- paste here -->
+
+* Description (optional):  <!-- short summary -->
+
+* Screenshot or gif (strongly recommended): <!-- drag & drop or link -->
+
+<!--
+
+### Tips 💡
+
+* See how to release apps: https://ratatui.rs/recipes/apps/release-your-app
+* Share it in our Discord: https://discord.gg/DkvdWRPJ 
+* Share it in our Forum: https://forum.ratatui.rs/
+* Add this badge to your README for showing off:
+
+```md
+[![Built With Ratatui](https://ratatui.rs/built-with-ratatui/badge.svg)](https://ratatui.rs/)
+```
+
+-->