CLAST: major refactoring

Hi

I just pushed a major rework of the CLAST internals.

The system is now pretty much usable, of course with an emphasis on the "pretty much". I will welcome any bug report to improve it.

Tested on LW, SBCL and Allegro 11.x. CMUCL and CCL will work as well (just need a little time). Probably also ECL. The naughty Java crowd giving us ABCL instead needs to do some work (naughty, naughty, naughty)! People working on other implementations, please drop me a line.

https://clast.sf.net

(The documentation is not up to date, but that's minor)

Enjoy