Cclean up after assignment
- Removes setCode as the assign member function is better suited.
- Changes to use a macro for implementing the addition & subtraction operators.
- Changes to use a macro for the relational operators.
- Changes the greater than to be implemented in terms of less-than.
- Changes to use a macro for the inequality operator.
- Changes to use a macro for the maths & assignment operator.
- Changes to use a macro for the freestanding maths operators.
- Removes the isPositive member function, as the relational operators can perform that function.
- Fixes unchecked multiplication in the negation operator.
- Fixes missed functions named minor truncated to minor only.
- Removes the assignment with move operator, as it is unnecessary with the underlying types.
- Fixes missing checks when rounding a monetary amount.