#407 Add PsExec as an alternative to SSH for command dispatching

[Anthony Shortland]

PsExec (http://technet.microsoft.com/en-us/sysinternals/bb897553.aspx) is a broadly adopted implementation of remote command execution on the Windows platform. It uses either user/password to security token (password-less) authentication and best of all does not require any software installation on the remote system. This is in contrast to using Cygwin/OpenSSH which does require a complex software install and configuration effort and hence is something of a barrier to adoption of ControlTier on the Windows platform.

This feature should implement PsExec as an alternative to SSH for all command dispatching and make its use for dispatching to os-family=Windows nodes at least a global property setting in framework.properties if not selectable on a node-by-node basis.