Zooming moves axis offscreen

Reported by Caio SOUZA

BUG DESCRIPTION:
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If there are some axis, zooming moves them off screen

ERROR LOG:
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HOW TO REPRODUCE THE BUG:
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f=scf();
plot(0.1:0.1:1,0.1:0.1:1);
a1=newaxes();
a1.filled="off";
yy = f.children(2).y_ticks.locations;
drawaxis(x=1,y=yy,dir='r');
Then zoom ...


OTHER INFORMATION:
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This is not exactly a bug, since you pass a position to the draw axis, but it would be alot more useful when the axis has any of x or y coordinates constant to keep the axis still where it was and zoom/stretch only the coordinates which are not constant.