(- re fix) Shortening the reactor debugging output quite a bit
(- re style) Cleaning up the section-headers.
(- fix) Repairing minor bugs impacting the examples
(api new) Re-designed the Thing() constructor's API from scratch.

Now, it's much less fragile and dependant upon the form of arguments. Documentation to come?
Probably not.

Important: This commit encapsulates two minor, but notable, changes in semantics deriving from the
new API:

 - The resumption-value of juxtaposition receivers will no longer (ever) have a noughty (it appears,
   previously, that it might have in some cases)
 - The default constructor for an execution's locals will no longer make the self-referential
   relation *within* locals (i.e. `locals locals`) apply responsibility. It seems to me, there's no
   point.