update PR template

.github/PULL_REQUEST_TEMPLATE.md

@@ -1,7 +1,14 @@
+<!-- Thank you so much for contributing! We're glad to have you onboard :) -->
+<!-- Please help us understand you contribution better with these details -->
+
 ###### Explanation About What Code Achieves:
 <!-- Please explain why this code is necessary / what it does -->
   - Explanation
 
+###### Screenshots/GIFs:
+<!-- As this is mainly a visual lib, please include a screenshot/gif if your contribution modifies on-screen components -->
+  - Screenshot
+
 ###### Steps To Test:
 <!-- What would someone do to be able to see the effects of your code? -->
   - Steps