FIX: dy added twice for right coords

[waygood]

Hi,
This is for the website version, not the github version, which is correct.
I've been looking through this, which is fantastic for what I need.
When testing, the guage goes all wonky if your browser is much taller than wider (Y padding only)

The solution is to change the Yo and Yi formulae
OLD:
Xo = w / 2 + dx + Ro * Math.cos(alpha),
Yo = h - (h - Cy) + dy - Ro * Math.sin(alpha),
Xi = w / 2 + dx + Ri * Math.cos(alpha),
Yi = h - (h - Cy) + dy - Ri * Math.sin(alpha),

NEW:
Xo = w / 2 + dx + Ro * Math.cos(alpha),
Yo = h - (h - Cy) - Ro * Math.sin(alpha),
Xi = w / 2 + dx + Ri * Math.cos(alpha),
Yi = h - (h - Cy) - Ri * Math.sin(alpha),

The reason is that Cy already has dy added to it ( Cy = h / 1.25 + dy )

[toorshia]

#245