Updating Skeletons and Plugins

- Mention the Pleeease plug-in (a nifty-looking CSS post-processor)
- Link to NPM search for "brunch" to help surface more plug-ins
- Update skeleton stars (go go Node-Webkit go)
- Rename @jupl skeletons and group together
- Remove unnecessary link to Sass library
Merge pull request #64 from jhabdas/brunch

Updating Skeletons and Plugins