Filled out .palette listing based on swatches in demo

Based on the way you constructed the `.palette-clouds` (with a `background-color` declaration and a separate `color` declaration), I first just went ahead and took the same approach for all of the color swatches featured in the demo; adding the swatches from the demo that are missing in this partial. However, I realized that if done that way, the results are often too hard to read because there is not enough contrast between the `background-color` and the `color`. So I simply added the missing palette background-colors based on what's featured in the great looking demo.