tided up line width for AA in do_cyl.c
Changed antialiasing.  GL_FILL AA not working on desktops (?OS difference from laptop? )
Now uses POLYGON_FILL without AA then GL_LINES to draw boundary. This way no changes in state needed.
Added more test loops to explore AA. Now aamode = 4 is best on lab machines. Set as default. This uses two lines. Still get quantization errors at corners.  With aamode 7 get quantization errors only vertically, so h disp is good. But unsmooth vertical motion then.
tidied up expo with frames > MAXFRAMES (runs until stopped by mouse press)
fixed psychophysics when nf > MAXFRAMES