2 instead of 4 spaces in .csscomb.json

BS3 commits: caadd720846ba698ff02942139b36ff680b12521
No leading pluses

BS3 commits: 4a01acaf6772a9c4f317ae94381376b16109da3d
Write Glyphicons to _data, generate Glyphicons markup

BS3 commits: 523eca14e81dcb448468e6881f7e071e5d7896e4