representation: Improve documentation
representation: Improve documentation

After adding the offsets argument I puzzled for a while how those
offsets work. I would have thought they offset the input, so that state
[2] with offset 2 would look like a state [4]. But the offsets are
applied after the scaling, so they have to be pretty small fractions.
Try to make that clearer in the docstrings.

gehring/tilecoding