Spine CSS as a table of contents

Building Spine CSS as a table of contents from partials, so the
different parts are not obscured by multiple build steps. Additional
reorganization can happen in future PRs, so it's easier to integrate
changes at deeper levels, and so we get the advantages of smaller files
earlier.

08/20/2014 - updated commits to match recent changes to develop branch - JF
Remove trailing spaces throughout
Merge pull request #125 from washingtonstateuniversity/pr/108

[PR] Spine CSS as a table of contents (part 2)