[Tests] Inverted Head with Inhomogeneous Axes

[discoleo]

Test: Inverted Head

• add a test with inhomogeneous axes;

##### Inverted Head #####
plot.base()
x = c(0, 6); y = c(1, 6);
arrowInverted(x, y, d=1, lwd=2);
arrowInverted(c(x[1], 5), c(y[1], y[1]), d=1, lwd=2);
arrowInverted(c(x[1], x[1]), c(y[1], 5), d=1, lwd=2);

### Inhomogeneous Axes
plot.base(ylim = c(0, 100))
scale = - 100/13;
d = 3;
x = c(0, 6); y = c(1, 60);
arrowInverted(x, y, d=d, lwd=2, scale=scale);
arrowInverted(c(x[1], 5), c(y[1], y[1]), d=d, lwd=2, scale=scale);
arrowInverted(c(x[1], x[1]), c(y[1], 50), d=d, lwd=2, scale=scale);

[DarianFlorianVoda]

Added! Thanks!