[Nitro] Patches for STI to sql.rb (in og)

[Rob Pitt]

Hi nitro people :D

Chris and I today had to perform a couple of minor modifications in order to 
get single table inheritance to work properly (we think... ). If you looked 
at it earlier, we have added another change since then in order to fix bad 
SQL queries being generated. We have put our changes up on:

http://www.lego.motionpath.com/view/Nitro%2BOg+Patches

Perhaps you would like to look at them should you get chance G?

Cheers,

Rob.