Feature/salt windows guest provisioning

Crude implementation of Salt minion provisioning on Windows. Deploys salt minion keys, checks system architecture, downloads correct salt binary, installs it & starts the service. Could use a lot more error checking, support for the salt boostrap command line options etc. but this works for me so I thought I'd share. Only tested this on Windows Server 2008 R2 64bit (english) in combination with vagrant-vsphere provider.