Deleted icosasphere.tsv because its purpose is over way back.

The root directory is getting crowded with imported libraries, so
I want to clean it up.
The Icosasphere thing had been contributed to astrodraw.cpp's
drawIcosaSphere and spheroid methods, so it's apparently no longer
needed.
Anyway, I don't even remember the file's meanings.
Moved obsolete scarry.hb hitbox definition file under models.

I could have it deleted since Scarry (Space Carrier) class is
not used for years.
It's also pretty obsolete since Squirrel initializer script was
introduced.  The hitboxes should be defined in a script.

At least we want to clean the root directory.