RTL support

Hi,

Regarding support for Arabic, Hebrew, etc. there are three elements:

   a.  RTL layout
   b.  Shaping
   c.  Bidi reordering

For myself, support for the first two, without bidi reordering, would be 
  fantastic.  Usually when I work in Arabic, I don't need bidi support. 
  IMO it should be considered an add-on.  Actually I think the way Vim 
does it is the way to go - each feature can be dis/enabled independently.

So how hard would it be to add plain RTL layout first, and then Arabic 
shaping?

thanks,

gregg