Playing with insettabular

[Dekel Tsur]

I got annoyed by the cursor handling in insettabular, i.e. the two dummy
position in each cell, one before the insettext and one after.
So I decided to change that and use only one dummy position.
I think that the result is more intuitive to the user.
What do other think ?

Of course, this patch should not be applied until it is reviewed by Juergen
(when he returns from vacation).

patch.gz