committed: Ada updates

[Richard Kenner]

    We will need to emit GENERIC first.  That's the part that removes the
    semantics of the input language.  Once we are emitting GENERIC trees out
    of the Ada FE, it should all "just work".

Right.  My question, then, is how close are the nodes that I cited to those
that are in GENERIC.  Is it just a matter of namings of nodes and fields
or something more substantive?