Sass version of themes and swatchmaker

Hi I wanted to use a sass version of Kickstrap so I decided to translate it. Since it comes with Bootswatch, I translated it too.

This pull request includes the sass version for all themes and the updated swatch maker to make it easier to create and test the sass versions. As far as I can tell the themes are identical. I'll push the css generated from the .scss files so you can check it if you want.

My hope is that by adding this to the main repository other people who would like to use sass will help maintaining it or at least reporting bugs.

Cheers!