threadsafe patch from Karl von Randow applied

Fix integer types to use definition from c.h. Per bug report by Patrick Boulay <patrick.boulay@medrium.com>

planning to modify them itself.  Otherwise we end up with shared RTE
substructure, which breaks inheritance_planner because the rte->inh
flag needs to be independent in each copied subquery.  Per bug report
from Chris Piker.

attr_needed/attr_widths optimization failed to allow for Vars with attno
zero in this case.  Per report from Tatsuo Ishii.

order.  Remove some unnecessary #includes (that duplicate c.h).

< * COMMENT ON [ CAST | CONVERSION | OPERATOR CLASS | LARGE OBJECT | LANGUAGE ]
> * -COMMENT ON [ CAST | CONVERSION | OPERATOR CLASS | LARGE OBJECT | LANGUAGE ]
263c263
< * Allow pg_dump to dump CREATE CONVERSION (Christopher)
> * -Allow pg_dump to dump CREATE CONVERSION (Christopher)

'double' arithmetic, per recent discussion.

prevents view from showing constraints on domains.  This addresses the
other half of Claus Colloseus' bug report.

for bit(x), the typmod stores x+4, like for the character types.)

reduce the number of times TopoSort() has to be executed by trying to
extract multiple dependency loops from each pass, instead of only one.
This saves about another factor of ten on the regression database.
This could be considered as another exercise in grokking Fred Brooks'
maxim: Representation *is* the essence of programming.

functionality. Per bug report by Alvar Freude:
http://archives.postgresql.org/pgsql-bugs/2003-12/msg00022.php

bottleneck in the new pg_dump code.

> * -Use dependency information to dump data in proper order

and pg_settings view.

one (use a priority heap to keep track of items ready to output, instead
of searching the input array each time).  This brings the runtime of
pg_dump back to about what it was in 7.4.

pg_depend to determine a safe dump order.  Defaults and check constraints
can be emitted either as part of a table or domain definition, or
separately if that's needed to break a dependency loop.  Lots of old
half-baked code for controlling dump order removed.

to certain compile-time options (FUNC_MAX_ARGS, INDEX_MAX_KEYS,
NAMEDATALEN, BLCKSZ, HAVE_INT64_TIMESTAMP). Also added "category",
"short_desc", and "extra_desc" to the pg_settings view. Per recent
discussion here:
http://archives.postgresql.org/pgsql-patches/2003-11/msg00363.php

and hash bucket-size estimation.  Issue has been there awhile but is more
critical in 7.4 because it affects varchar columns.  Per report from
Greg Stark.

transaction has been committed without SPI_finish() being called
first. Per recent discussion here:
http://archives.postgresql.org/pgsql-patches/2003-11/msg00286.php