Use SCSS for main CSS file

SCSS is a CSS pre-processor that allows for things like defining
variables. Jekyll automatically converts SCSS files into CSS files.

This is a simple rename, further changes will clean up the file and
begin using SCSS features.

The two "---" lines at the top are the trigger for Jekyll to process
the file. It is an empty YAML front-matter.
Expand tabs and trim whitespace in SCSS file
Refactor main SCSS file

This is a simple "run-length encoding" transformation of the SCSS file
where adjacent and repeated rules were turned into nested rules. So

  foo bar { ... }
  foo baz { ... }

became

  foo {
      bar { ... }
      baz { ... }
  }

The integrity of this change was checked by comparing the output of
cssunminify main.css before and after. Later refactorings will reorder
the rules to clean things up some more.
Define font families using SCSS variables
Run SCSS through sass-convert

This converter can convert to/from the sass and scss formats. By doing
a "convert" to SCSS we get the file consistently reformatted. The
command line options used were:

  sass-convert -T scss --indent 4
Further refactor SCSS file

This merges non-adjacent rules where possible.
Merge pull request #7 from mgeisler/scss

Use SCSS for main style file