(new incomplete api vis) Little Reactor's first steps!

There's a lot of code to be copied from µPaws' reactor sections, and most of them are extremely
tightly-coupled and messy. We'll see how this goes.

Squashes: 239e0, ad57c
(api fix) Make Thing##construct responsibility-aware

It's obvious that a dictionary-ish `Thing` should be responsible for the ‘pair’ structures therein
(after all, they are clearly a part of the same data-structure). The default responsibility of that
structure as a whole for the `Thing`s passed to `##construct` is, however, less clear.
(new api) A simple Table type to mediate responsibility

(Also implements, after several re-writes for different approaches, the traditional `Mask` type to
populate that table.)

Squashes: 10f79, fb7bc..cc370
(new api) Implement Execution#advance

This is a nearly direct copy from µPaws, which is a disappointment, as I *really* want to completely
overhaul this algorithm from scratch some time. At the very least, it needs to be broken down to
individual, separately-tested component functions.

Squashes: f2242..103db
(re vis) Updating the `locals` semantics.

This is the beginning of the work required to update this implementation to design10. Most of that will occur in another branch, but some of the changes I can't work without, including this one.
(- fix tests) Omission of .coffee in a require was breaking browserify
(- tests new) Adding a test for the odd case of `(((foo)))`
(- fix api) advance() no longer `bind()`s Aliens' bits
(new api) Implement the core's default receivers

Provides for `Execution` and `Thing`. `Label` has none of its own, inheriting from `Thing`.
(new api) Implement Unit#next
(new api) Implement Unit#realize

Getting there. Again, mostly verbatim from µPaws, but this time, it's been massively cleaned up. The
reactor's almost functional! :D
(fix api) Collect several small fixes

Including:

(meta fix api) Changing data.coffee from API-modification to exports

For reasons that I can't discern, the coverage system was choking on the old format, here. For
whatever reason, when executed via CoffeeScript, everything worked fine; but when compiled to JS,
`data.coffee` wasn't being loaded in time for `reactor.coffee` to have the data-types made available
to it at require-time. Very strange.

This is probably slightly more idiomatic *anyway*, so a net benefit.

+ fixing Table#remove
+ the Thing receiver properly calls #find
+ Unit is now parameterizable (for #stage)
+ fixing #stop
+ fixing indiscriminate give() in the reactor

Squashes: ed5a3..f082f, 983ac..f95c3
(- new api) Provide Paws#infect as convenience to consumers
(- noop meta fix) Ignore build-products in Test/
%%SYNC