Hidy hole in which to stick "uncontrolled" values

Hidy hole in which to stick "uncontrolled" values

In order to make use of the massive speed increases provided by
intarray indexing, we need to use (you guessed it) integers.  But
uncontrolled record attributes are not necessarily (or even very
often) numbers.  We will store them in a table of unique (per
attribute) values, and use the id from that table in our intarray
indexing.  That id comes from a DECREMENTING serial that starts
at -1 and counts downward.  This avoids collision with the other
set of integers (the id from config.coded_value_map) that we will
use for controlled record attribute values.

Signed-off-by: Mike Rylander <mrylander@gmail.com>