Added SHORT-FLOAT-ADD-INSTRUCTION.
Added SINGLE-FLOAT-ADD-INSTRUCTION.
Added DOUBLE-FLOAT-ADD-INSTRUCTION.
Added LONG-FLOAT-ADD-INSTRUCTION.
Added SHORT-FLOAT-SUB-INSTRUCTION.
Added SINGLE-FLOAT-SUB-INSTRUCTION.
Added DOUBLE-FLOAT-SUB-INSTRUCTION.
Added LONG-FLOAT-SUB-INSTRUCTION.