Add ASCIINEMA screencast instruction

.github/ISSUE_TEMPLATE/bug_report.md

@@ -20,10 +20,20 @@ Steps to reproduce the behavior:
 
 A clear and concise description of what you expected to happen.
 
-**Screenshots**
+**Screenshots/Screencast**
 
 If applicable, add screenshots to help explain your problem.
 
+OR
+
+Attach a session recording using https://asciinema.org/
+To use it:
+```sudo apt-get install -y asciinema && asciinema rec # start session recording
+```.venv/bin/python -m photobooth # start photobooth directly
+```Ctrl+D # stop recording
+```y # yes to upload and get URL to paste here
+```
+
 **Hardware (please complete the following information)**
 
  - Device [e.g. Intel Laptop, Raspberry Pi 3B+, Odroid C2]