provisioner/shell: execute script directly instead of using /bin/sh
Local mode for VBoxGuestAdditions. Provide local path and SHA256
website: specify ruby version in the gemfile
website: add a shutdown command to the vm builder config examples
Merge pull request #147 from mitchellh/shutdown-docs

website: Shutdown Command in Examples
Merge pull request #145 from sgirones/feature/local-mode-guest-additions

builder/virtualbox: Local mode for VBoxGuestAdditions. Provide local path and SHA256
builder/virtualbox: typo in test
builder/virtualbox: test the configuration

/cc @sgirones
fmt
builder/virtualbox: style nitpicks and CHANGELOG
website: document the guest additinos URL and SHA256

/cc @sgirones
builder/common: Error on non-200 download responses [GH-141]
communicator/ssh: show more descriptive error if SCP not avail [GH-127]
Started on a contributing doc
post-processor/vagrant: properly close file handles [GH-100]
Merge pull request #133 from ubermuda/provisioner/shell/script-execution

provisioner/shell: execute script directly instead of using /bin/sh
provisioner/shell: inline_shebang for inline scripts
website: document the inline_shebang stuff
builder/virtualbox: whitespace
builder/amazonebs: retry SSH handshakes [GH-130]