StudentCTEProgramAssocation Extension issues

Currently if a user want to extend CTEProgram within StudentCTEProgramAssocation, the entire StudentCTEProgramAssocation type will need to be recreated because the reference will need to point to the new extended CTEProgram type instead of the original CTEProgram complex type. The reason for this is that since CTEProgram is required it cannot be excluded and replaced in an extension to StudentCTEProgramAssocation. A potential fix is to make the CTEProgram MinOcc = 0 instead of 1.

There are additional issues with the naming and annotations with CTEProgram and it's elements, since the complex type really represents a Career Pathway, not a program.