Add bare-bones versions of FemtoLisp

[lassik]

These are impressively small Scheme interpreters by Jeff Bezanson, now of Julia fame. They are experimental/pedagogical versions of the FemtoLisp evaluator with inessential features removed. FL is also great but requires several thousand lines of C, many files and a boot image.

These interpreters load a system.lsp file containing the standard library, but you can replace it with an empty file and they still work. In that case you have to write your code like this:

> (set 'factorial (lambda (n) (if (< n 1) 1 (* n (factorial (- n 1))))))
(lambda (n) (if (< n 1) 1 (* n (factorial (- n 1)))))

> (factorial 10)
3628800

[marcpaq]

Thanks for the request, but Lisp500 is already in the b1fipl.