SQL Databases from before 2.3.16

[Mike Alexander]

--On December 9, 2010 10:24:51 AM -0800 John Ralls <jralls at ceridwen.us> 
wrote:

> Anyway, if we're going to introduce the gnucash-version row, we
> should do it now, before 2.4 is released.

It seems like this is a good idea, even if it is never used for 
automatic upgrades or fixups.  At the very least it would help with 
debugging to know which version last wrote the data base.

     Mike