[systemd] Add canon-webcam user script

systemd/.config/systemd/user/canon-webcam.service

@@ -0,0 +1,12 @@
+[Unit]
+Description=Run gPhoto with a stream from a webcam
+
+[Service]
+Type=simple
+ExecStart=/home/powellc/.bin/slr-to-webcam
+ExecStop=pkill gphoto2
+Environment=SSH_AUTH_SOCK=%t/keyring/ssh
+Restart=on-failure
+
+[Install]
+WantedBy=default.target