commands/box/list: doesn't trigger Vagrantfile loading
command/rsync-auto: proper require
provisioners/salt: error if minion_config missing
website/www: feature preview windows guests
Merge pull request #3506 from rasschaert/master

provisioner/salt: better error if master config missing
Update CHANGELOG
v1.5.4
website/www: version for deploy
Add autostart as an option for vagrant boxes

Added specs for the environment and vagrantfile. Added a methd to retrieve
autostart_machine_names. Changed the plugin up/command to use autostart_machine_names
when no argument was given to the command.
communicators/winrm: initial import from vagrant-windows
communicators/winrm: Config unit tests (a little)
kernel/v2: configurable communicator (doesn't do anything yet)
core: Configurable communicator
communicators/winrm: autodetect port based on forwarded ports
communicators/winrm: more tests
communicators/winrm: fix powershell execution
guests/windows: initial vagrant-windows extraction
guests/windows: fix invalid templating
guests/windows: configure networks
guests/windows: fix network configuring