Add inner node-id to Local declarations as step towards new dtor semantics.
Check point: added Stmt and Local to pretty printer.

Note that the local case prints the init id added in prior commit
(which would need to be stripped out if this is rebased to an earlier
commit).
Attempt to incorporate the node-ids for locals into the region tree.
Revised ast_map so that `NodeLocal` actually carries a `&Local`
instead of a `&Pat`.
Continued hackage on two-node locals.
Followup hackage for two-node Local