quotient and modulus for non-integers are wrong

Unless I'm way off about what we want `//` and `%` to mean, I think these are all wrong:
https://github.com/Macaulay2/M2/blob/ec9e9ac60ed4a8e791448942202f077a88a87e15/M2/Macaulay2/m2/reals.m2#L213-L226

Some examples: (afterprints are silenced)
```m2
i1 : 13.3 // 4.0

o1 = 3.325

i2 : 13.3 % 4.0

o2 = 0

i3 : 13.3 // 4

o3 = 3.325

i4 : 13.3 % 4

o4 = 0

i5 : 13.3 // (4/1)

o5 = 3.325

i6 : 13.3 % (4/1)

o6 = 0

i7 : (pi*ii) // 3.0

o7 = 1.0471975511966*ii

i8 : (pi*ii) % 3.0

o8 = 0
```
What's the point of having `//` be a synonym for `/`, and why even define `%` for non-integers if the answer is always zero anyway?!