[Bf-python] rvk1 to rvk2 script

[Matthew Fulmer]

The bundled rvk1 to rvk2 script (Script->Mesh->Rvk1 to RVK2) no
longer works. It may have been somewhat superseeded by the shape
keys refactor, but a description of its behavior is at 

http://www.elysiun.com/forum/viewtopic.php?p=447745#447745

It basically is supposed to convert a mesh that is duplicated
(Shift-D) into an rvk, but now it always says "You must select
two meshes"

-- 
Matthew Fulmer