Mainly was caused by the flakyness of image rotation in cases
when image has even size. The test was expecting the transform
code to rotate the image around pixel corner, which isn't a
common behavior in image processing applications. Rotation
is usually done around the pixel center.

So now made it so RotateImage() rotates the image around the
pixel center which gives 100% proper result for odd sized images
(i.e. center pixel stays untouched).

Also made the tests to use odd image sizes which are more
predictable by the humans. We can use even sized images in the
tests as well but their result wouldn't be so much spectacular.

Another issue with the tests was caused by RescaleImageTranslation
test which did expect things which are not happening in the
function.