retro: wow! graphics work fine now!

[Paul Dufresne]

just a short message to share my joy of seeing good graphics in retro.
clrscr WAS not removing the garbage but it does it well now.

65 gputc
4 0 0 319 199 box
they work great!

colorbars
I was surprised to see that the bars take all the screen, and
moreover that they are horizontal, not vertical like they were
before!
So that too work great.

The textmode corruption is still a problem. It happens only
when executing some words in graphics mode.