[geotk] Mapping coordinate system axis order to i,j indices on a map images

[Martin Desruisseaux]

I forget to said that one issue is that ISO 19123 does not have this 
"GridGeometry" object which existed in OGC 01-004. "GridGeometry" and 
"SampleDimensions" are the two legacy OGC 01-004 objects that I'm tempted to 
port to the new ISO 19123 framework. This is similar with what we did for the 
referencing module, where MathTransform has been ported from the legacy OGC 
01-009 to ISO 19111. Please let me known what you think.

	Martin