Add PR template

Author: joshka

.github/pull_request_template.md

@@ -0,0 +1,19 @@
+# New Awesome Ratatui PR
+
+Hey there, thanks for making Ratatui Awesome!
+
+Take a brief read of our recipe for [Releasing your
+app](https://ratatui.rs/recipes/apps/release-your-app/), which includes some tips on installation
+commands and making better screenshots and gifs to show off your app. The biggest thing is to have
+an image or gif in the PR description that shows off your app in action.
+
+Please also add a link to your crate / github repo in the PR description as it makes it easier for
+us to click directly to it. Also consider dropping a link in the [Ratatui
+Discord](https://discord.gg/DkvdWRPJ), or the [Ratatui Forum](https://forum.ratatui.rs/).
+
+You can use the following markdown to add a badge to your README, which will show that your app is
+built with Ratatui:
+
+```md
+[![Built With Ratatui](https://ratatui.rs/built-with-ratatui/badge.svg)](https://ratatui.rs/)
+```