[BUG][FIX] Thumbnails in Holders (EToy)

It seems like noone used thumbnails in Holders before? My son needed this
to hold levels for a game. Since each level is almost full-screen,
thumbnailing them was the only viable solution I could think of. So here's
a one-line fix to make it work:

"Change Set:            ThumbHolderFix-bf
Date:                   30 September 2002
Author:                 Bert Freudenberg

Makes getValueAtCursor and getGraphicAtCursor for a Holder showing 
thumbnails return the represented morph. Before, the thumbnail itself was 
returned which caused the animation to be played at thumbnail size."

-- Bert

ThumbHolderFix-bf.1.cs.gz
Description: GNU Zip compressed data