Windows elevated / non-elevated installation should be user selectable

[adamedx]

Users should be able to choose whether or not to install the chef-dk msi with elevated (root) privileges. Additionally, whatever install directory is chosen should be validated as to whether or not it has a space since Ruby and its toolsets behavior erratically when executables are located in a path that contains spaces.

From an MSI perspective, this forum post describes how this can be authored via Wix: http://stackoverflow.com/questions/14339372/wix-non-admin-installer-tutorial.

[irvingpop]

This should be worked on after #68 is fully resolved (ChefDK can be installed into a path with spaces or on a non-system drive)

[danielsdeleo]

Not doing this.