There will be subsequent commits to refine semantics, esp. version-specific semantics,
as well as I/O functionality and restrictions.
Note: I'm getting white-space differences in the preprocessor test results,
which I'm not checking in. I think they need to be tagged as binary or something.
Added some const as well. This will remove camouflage of the next commit,
which will add the bulk of Array of Array semantics and functionality.
(Note the basic grammar and data structure is already in place.)