Refactored a big chunk of newfpu
Refactored a big chunk of newfpu

- the framework for throwing exceptions should work correctly now
- NaNs and signaling NaNs should work
- condition codes are set now
- write-back and rounding (including throwing INEX2) are now implemented

(Note: you can't actually use any of this code yet, and it doesn't actually
       fully implement any fmath_* instructions yet)

landonf/shoebill,mietek/shoebill,jduerstock/shoebill,mietek/shoebill,pruten/shoebill,jduerstock/shoebill,pruten/shoebill,landonf/shoebill,pruten/shoebill,mietek/shoebill,pruten/shoebill,landonf/shoebill,jduerstock/shoebill