Remove dead code
Merge pull request #2212 from fgrehm/remove-dead-code-take-2

core: remove dead code
website/*: update therubyracer version to work with latest
website/www: update CSS to work with latest middleman
website/docs: fix build
website/www: work on a blog
guests/linux: try `id -g` to determine group as well [GH-2197]
core: don't delete state data if id=nil [GH-2201]
Revert "core: better cleanup of ".vagrant"" [GH-2201]

This reverts commit 5b42994406f977907fccfdce6e85f5d32d9cd84d.
provisioners/ansible: default output level is verbose [GH-2194]
hosts/arch: remove duplication with HostsLinux
core: Vagrantfile must be file [GH-2216]