[berkshelf] Berkshelf is for Workstations

This makes the Vagrant driver behave more like the LXC driver, relying on the SSH Base semantics set forth in test-kitchen@1.0

I prefer to have berkshelf resolve cookbooks on the workstation -- temporarily install them somewhere, and then have an intermediate system, in this case, TK, ship cookbooks and so-on from a combined, resolved, cookbook directory. Previously Vagrant was trying to interact with Berkshelf on the guest, which would mean that the guest would need to have access to Git, etc
[berkshelf] only configure the home directory etc if not using Vagrant directly for provision
[berkshelf] Hack the synced folders
[berkshelf] use_vagrant_provision toggle for chef  related functionality, enhance synced folders
[synced_folders] Fix quotes in Vagrantfile generation
Merge pull request #12 from fujin/feature/berkshelf-is-for-workstations

[berkshelf] Berkshelf is for Workstations