add recipe for e2wm-sww
Merge pull request #1734 from aki2o/e2wm-sww

add recipe for e2wm-sww
Add a recipe for markdown-toc (a toc generator for markdown)
Update `serverspec` recipe.
Merge pull request #1735 from ardumont/add-markdown-toc

Add markdown-toc recipe
Merge pull request #1738 from k1LoW/update-serverspec

Update `serverspec` recipe.