nponeccop

``` foo x = { bar = { quux x = sum x 42 mul (quux 2) (quux 3) } mul bar bar } ```

subj

Migrated from Google code

Implement a back-end to support generation of .coffee sources

Implement a front-end to support compilation of .spl files (basically, an APL/J/K-inspired syntax for HN).

If a polymorphic definition is used only monomorphically (e.g. `id x = x` is only fed ints) its @definitionType should be `int->int` and not `forall a . a -> a`....

Useful tests from `spl-test-adhoc-spl` should be ported to HN syntax and included in the main test suite by creating more files in `hn_tests`.

Current SPL interpreter and REPL shell (`spli` cabal target) is very low-tech and depends on deprecated code (e.g. on an old type checker in `SPL.Check3`).

Currently same sources are built again for every executable. However, a lot of code is shared between test suite and command-line compiler, so a precompiled library would reduce build time.