Make it possible for Windows machines to have 'program files' as their install directory.

It has been requested by the IT service department at the Royal Library that it should be possible to install and run the NetarchiveSuite applications from the "program files" folder instead of the current case where the installation is performed in the local "user" folder.
The directory "program files" can be placed on any hard drive accessible to the machine but the environment variable %ProgramFiles% should always point to the right directory. This will eleminate the "space" problem for Windows access.