Add a Setup project that creates an installer.

After a rather arduous process, I've finally created an installer for Puzzle Path that we can distribute to the testers and end-users. A `Setup` project has been added that generates this installer. The installer itself puts the game files in a subdirectory of Program Files, and adds a shortcut to the user's Programs Menu.

Commit notes:
* The Setup project has been configured to build only in Release mode.
* In addition to everything else, the installer currently copies a single test level to the user's AppData/Local folder. This level is not used, but it is a proof of concept of how to store the levels in a user-accessible area.
    * The AppData/Local folder is also where user progress and preferences should be saved.