This is a fix for #2399: when there's no variants we should not try to scan them.
I have set the RDP US keyboard for the South African layout, if someone has a better
layout...
Note: we should probably set something that is not zero for other layouts
The Programmer Dvorak keyboard layout is supported by Xkb but support
in Windows is only available through an open-source add-on driver. It
is plausible that those that use this layout in X11 also installs this
driver on Windows instead of using the standard Dvorak variant there.
This changeset recognizes Programmer Dvorak as its own variant, and
assigns this a layout ID which matches the one used in the Windows
driver so that it will be selected when you logon. If this layout is
not available, it will now revert to the regular United States layout.
Tested with Ubuntu Precise 12.04 connecting to Windows 7 SP1.
