#50 auto rotate shifts the requested dimensions

[Ciprian Dobrea]

When requesting something like
tn.php?src=pic.jpg&ar=x&w=500
if the original is 3264px×2448px (tilted right 90deg)
the result will be 413px×550px instead of 550px×413px

Can we check for automatic +/- 90% rotates, and shift the requred size(s) ?
or do the rotate before the scaling.