interpolate and populate color stops
dynamically generated stylesheets

Except we probably want to fix unvoted-upon content as black and
compute the positive and negative scales separately, instead of the
lowest-scoring thing on the page being bright red (even if it's only
because nothing has been downvoted).

(And, some whitespace fixes and more informative __str__ methods.)
anchor the unvoted to black; share template fragment

(I was kind of torn whether to call the subdirectory "includes",
"fragments", or "partials" ... I guess "includes" is OK.)
Merge pull request #1 from zackmdavis/fluid_color

dynamic stylesheets, share template fragments