Support multiple implementation languages on one node

[davidnicol]

Currently, compiled motes (sequences and macros) are stored as Perl source. With the possibility of a Node.js port, it becomes desirable to have multiple implementations using the same persistence store. Making this work will require storing multiple compiled versions, and compile-time source, for compiling in a new implementation language the first time a compiled mote is used in that implementation, instead of simply compiling to implementation-language source.

Close this ticket when we are (1) compiling sequences and macros into an intermediate nameless form; and (2) compiling from said INF into implementation language with something like (eval (preprocess INF)) rather than simply evalling what's read from the database.

Caching the preprocessor result is not necessary (following the "correct, then fast" dictum) but if it is done it should be in the code that is concerned with thawing nonprimitives rather than in the main persistence configuration.

[davidnicol]

"Adapters" are also involved; there seem to be two options, and their synthesis. The two options are (1) every adapter dispatches based on implementation, at INF compilation time, and an exception is thrown when an adapter does not appear in the current implementation (2) insist that all adaptors use a named socket interface, or an external program interface, or a similarly clear abstraction (3) support both 1 and 2 (4) use a fallback strategy, where per-adapter dispatch first checks for "native" implementation of the adapter, and then falls back to a generic implementation, then throws the exception.