#48 compliance of quotient, modulo, remainder to r5rs

[lloyd konneker]

I help maintain the TinyScheme embedded in Gimp.

An issue Gimp #5230 about the exact/inexact ness of said functions, i.e. says they accept floats and return floats when they shouldn't.
The issue reporter cites r5rs.

Reporting it here, since any issue is really here, i.e. the upstream of the Gimp clone of this repo.
And we probably won't change it in the Gimp repo, unless it is changed here.

I don't agree that the issue needs fixing.
In my testing, the code behaves reasonably.