converted VADD to function within ALU
ALU case statements
Merge branch 'Greg' into Max

Conflicts:
	ALU.v
fixed a few things as a result of my last merge
refactor VADD for easier testing
trying to fix VADD
refactored funcs into seperate file and got a very basic version of VADD/float_add working (no sign, no rounding, no overflow)
handling negative mantissas better?
Fixed and refined sign logic
working except rounding and overflow, rounding in progress, don't pull from this commit
compiles now