[Chicken-hackers] Library list support

[Evan Hanson]

Hi all,

The "chicken-5-library-lists" branch adds support for list-style library
names, e.g. (use (chicken ports)) and the like.

I'm still making minor improvements here and there, but in general I think
it's ready to be merged. I'd appreciate it if someone could have a look.

A few things to note:

  * Support for defining new module aliases (i.e. the `(module foo = bar)`
    syntax) has been removed to avoid ambiguity with functor instantiation.
    See <address@hidden> and
    <address@hidden>. The machinery has been left in
    place, however, so it won't be much trouble to restore the feature with a
    different syntax later (or swap it in for a different functor syntax, or
    whatever).

  * With that single exception, everything is totally backwards-compatible,
    and I haven't changed any existing documentation or tests to use the new
    library syntax yet.

  * The branch adds an "internal" unit ("chicken.internal" module) for new
    runtime support code.

Cheers,

Evan