Implemented fgetman,fscale,fsincos, and partial-fixed a softfloat bug

- fgetman, fscale, and fsincos are implemented but not tested at all

- fixed part of a softbug float when converting subnormal numbers between
  floatx80 and float128

- also, I checked in the wrong core/Makefile with the last commit.
  Re-committing the correct Makefile