coyote: CGIMAGEINFODESCRIBEVALUES

Provide information about the selected xy-pixel from an image, or a hash of
images.
Params:iimage: in, required, type=image
   A 2D or 3D image array
xpixel: in, required, type=int
   The X location on the image to fetch information from
ypixel: in, required, type=int
   The y location on the image to fetch information from
hsh: in, optional, type=HASH
   If a valid HASH, it should contain key/Image (string/array) pairs that
   will be described.