With this version we start having more types to our machine, so we
can start perform some actual calculations with it. Those
calculations are still very primitive since we have no way to pass
more than one argument to a procedure and we don't have any way to
perform conditional processing.

Nonetheless, this version adds support for 32bit signed integers,
64bits double precision floating point numbers, characters and
booleans. We also throw in some functions to act on those in
order to test the machine, but those are crude and not meant for
real usage thu far.

After this, we have:
1) a representation for 32bit (fixnum) signed integers;
2) a representation for boolean values;
3) a representation for 64bits double precision floating point
   numbers (flonum);
4) successor and predecessor primtives for fixnums and flonums;
5) negate primitive for fixnums and flonums;
6) is_positive, is_zero and is_negative primitives for fixnums and
   flonums;
7) logical not function for booleans;
Merge branch 'master' of github.com:alexandream/nuvm