Progress: continue working on fss-003 Extended List

Progress: continue working on fss-003 Extended List

A nested type has been created.
I suspect that I will need to change the structure of the other types to improve consistency, but more review and consideration is needed before any such changes are made.

A read program was written but it is essentially a copy and paste of Basic List, with a few minor changes just to make it compile.
The program arguments of all the FLL programs will need to be changed such that adding support for "depth" selection can be used for things lile Extended List.

The memory allocation is implemented but not reviewed.
I converted the behavior to support nesting, but I need to review the logic to ensure I caught everything.

No time was spent on the write support.