Make nice asciimatics screen for when the program is closing but still saving video

[Davidy22]

When recording and video rendering and video writing are working in parallel, the video writing portion of the program will lag behind. If the program is closed while there are still video frames to save, the program will display a message and continue to run while it saves video. Make the end screen look a little prettier and more informative.

[dhananjaylatkar]

I'm not getting time from work. Let someone else do it.