Add geomgui 0.12
Geomgui is a viewer for the geom layer in the kernel written in C.
It can show the geom layout on the host computer or fetch info from
a remote system via ssh. It has the same arrow key bindings as fx, vi,
(h,j,k and l)and uses z to soom out and Z to zoom in, u is for updating.
Approved by: tmclaugh (mentor)